First thanks and good luck Obsidian. Played the crap out of every inspiration game mentioned and I have my fingers crossed you can capture any of that magic again, even bought Alpha Protocol after bad reviews because I love what you guys are trying to do, New Vegas was ten times better than FO3 btw.
Please excuse the late night tired ramblings of an overgrown boy Soldier stuck in Afghanistan but my connection sucks and am tired so I haven't read through every topic so I'm sure a lot of this has been discussed but I am super excited and want to throw my 2 cents in.
Bad things about the classics:
-Often abused rest mechanic. Lots of different ways to go about it, depends on how you are building the game. Personally suggest borrowing a few ideas from D&D 4th Edition, especially the basic concept of at-will attacks for mages.
-Battles after conversations that prevent pre-buffing which would then require re-loading and pre-buffing like crazy to win. Suggestions, take a good hard look at how buffing works, it can be fun, especially when doing something like figuring out to cast protection from a certain school of magic when Kangaxx the Lich Skull keeps casting imprisonment on you or Mindflayers try to stun you over and over. If buffing is going to be a big part of a character's abilities then think about how to more immersively make them useful. Also things like contingency spells or spell sequencers with a little more robustness would be good.
-Over abundance of money, or lack of good purchasing options, however you want to fix it, some good thoughts on it out there.
-BAD romances (BG 2 has probably been the only game to do romances well since Witcher 2 that I've played). Make a few good ones, if there isn't one that suits every single person's tastes than too bad, it could be a very useful and emotional plot tool if done right.
-Over chaotic battles, especially magically. Too many spells had the same casting animations/effects and it often got pretty confusing about what spells were actually cast and what to do about it. Tactical pausing allowing you to utilize your mage's knowledge to identify spell effects being cast or already cast would be nice. Possible cool feature would be to have casting effects appear more generic unless you have the perquisite skill or feat/ability.
-Don't tell me I'm losing a fight for plot purposes when I'm clearly not. Yes after multiple play-thrus I was experienced and crushing Irenicus and Malak in the early fights against them, only to be told I wasn't really because the plot dictated it.
-Auto-reviving companions. Yes healing could be a chore casting heal spells over and over but actually having to drag someone's body to be rezzed in BG 1 was kind of awesome, similarly awesome if a trusted companion was obliterated by a critical hit (yes it would probly result in a reload but that is up to the player's tastes IMHO).
-Terrible lack of application for magic outside of combat, especially when there was such great role-playing source material to draw from. Also a terrible lack of combat abilities/spells on non-combat situations. Burning/blasting a door open or something.
-Trade-offs between combat abilities and non-combat abilities. Always hated having to put my points into Big Guns or Doctor/Lockpick/Whatever. Personally suggest limiting the players choices, maybe 1 point per level for combat abilities and one point per level for non-combat abilities, some may call that too limiting but I'd consider it a gentle nudge in a better direction.
-Not really a fault of the games of the time given the technology but implementing physics and material systems could greatly improve the game. Destructible terrain is just awesome even if the actual in game practical implications are limited.
-Back-stabbing/thieves. A really great character class and game mechanic that is very crippled by the RTS pause style of BG/NWN. Flanking was arbitrary, ranged sneak attacks all but non-existent (I think?). I am encouraged by the talk I've heard about not having to fit another game's mechanics into a different computer style and hope that this will be reflected in the combat system.
-Omniscient guards/crime reporting/dumb behavior. Lots of games have struggled with this. The faction/regional reputation system is a good first step on this but please put some effort in this, with good logic for reporting crimes and intelligent fight/flight behavior for civilians when appropriate.
-Lack of variety for fighters. Something I like about DnD 4 was the attempt to give more tactical options to fighters other than basic attack. But please no bland WoW/Dragon Age cooldown abilities. Grappling? Buying for time fighting stance to hold that wave of goblins off your mage? Formations that matter and actually stop enemies from running straight to your archer/mage would be nice too obviously.
-Lack of area of effect templates, yah it made launching that fireball more difficult when you missed or clipped your fighters with it but I personally prefer having that information to make better tactical decisions.
Recent RPG Annoyances
-Branching quests for the sake of branching, less of a problem in BG/Fallout/Planescape but a big issue I have with a lot of the modern RPGs. Often the different options all obviously lead to the exact same place and break immersion. Often branches seem tacked on just to have everything covered. Write quests that you feel in your heart are good, if you can find good options include them and if not ok, I'd rather play through one well written quest with one path than a mediocre written quest with 8 paths.
-Drown with choices. Similar to above. I don't mind being a LITTLE limited by class/race/whatever in terms of quests/dialog/whatever, it helps replay. But it is worth pointing out that I probably
played through Fallout 1&2 and BG 1&2 and KOTORs several times making almost identical decisions because the game was GOOD.
-Too much micro-grinding and tedious crafting. Crafting can be cool but I think can speak for a lot of your target demographic that we are all adults now (I played sick for days when I got Fallout 2 in high school) and we don't have 4 hours a day to spend grinding to make items.
-Instant free for all fast travel. IMHO Morrowind had one of the best traveling systems ever created. As you gained experience, both in terms of your personal knowledge of the game and access to items/magic, you gained more fast travel options. If I was in the mage's guild I could teleport to other guilds, if I knew the routes of the flying jelly-fish monsters I could plan trips accordingly. If I became badass I could mark/recall. The developers carefully gave you more and more fast transport options as you as a player were getting more sick of having to walk. It felt like a well earned reward, instead of instantly being able to fast travel everywhere which to me is just a lazy way of solving the issue.
-Enemy level scaling. See Oblivion. Lazy game design that robs me of my sense of accomplishment and shatters immersion.
-Fake uniqueness. When I see two NPCs with the same name standing next to each other, neither of whom has anything to say other than flavor/background one liners it kills my suspension of disbelief. I'd much prefer "Guard" or "Townsperson", yes it can make the one named NPC who has something to say more obvious but is that so bad? Focus the player in on the dialog you have created, don't make me waste my limited gaming time searching for the right guy to talk to.
-Carefully planned progression in terms of acquiring items. Finding my first set of plate mail in BG was a great feeling. Finding my first Combat Armor in the bottom of the Glow in Fallout was great, not to mention finally getting my own power armor. The game showed me those things, showed me I wanted them and then made me earn them and it was great when I did. Compare this with finding a randomly generated mini-gun at level 5 in Fallout 3.
-BG had a really great main quest line that was at once both broad to fit all possible player class/race choices, and very personal. To me this was a really key element of the game's greatness, similar with KOTORs. In the end the main quest was intensely personal. It sounds like PE is going more that route and I say good.
-Obviously some great and memorable characters.
-Tons of great side quests, especially BG2 had some truly epic adventuring going on outside of the main plot line.
-Let me "abuse" some mechanics for awesome effects. Biggest example I can think of this is double-crossing both the mob boss (Gizmo?) and sherrif in Junktown of Fallout 1. Let them both kill each other off and come out with all the loot/reward, what a great feeling when I finally pulled that off.
-Awesome dialog. Planescape had just fantastic dialog choices almost all of the time. A lot of it probably didn't change to much about the game but it was great having a dialog choice that really just FELT like what you wanted to say. I can also specifically telling a drug dealing gang banger in Fallout 2 to shut-up and leave me alone or I would "Get angry on your face" and almost dying laughing. Dialog that complemented those power-trip fantasy feelings we all love in RPGs.
-Imagination brought on by scale. To me the pulled back isometric view lets my imagination fill in all the details. Don't let me zoom in to see my sword's 2000 pixel high resness. Let me see that new sword I found looks different, but from afar. My imagination makes that sword look more awesome than any artist can, especially if it has some great inventory flavor text.
-Great satisfying animations in combat. Peppering someone with bullets in Fallout 1/2 was so great. Even the critical hit gib/camera shake of BG was cool. I'd suggest adding things like severing limbs and some physics to make combat even more satisfying.
-Great ending to BG2:ToB, with cool write-ups for each character in your party about where they went afterwards, closed it up nicely. Same thing for Fallout 2.
Good luck, I'll be Kickstarting once I get on a more secure net!