Hey, I appreciate all the time you've must of taken to write this all out. You've clearly puna lot of thought into it and it really shows. I agree with some of your points and disagree with others, but there's one thing in particular I want address. While I agree the attributes could be much better, removing accuracy from the system was the best thing they've done so far. Even with the changes made to damage modifiers, if you add accuracy back into the mix it becomes a must have stat, regardless of the character concept. In fact, I can't think of a character archetype where maxing accuracy wouldn't be the most optimal choice.
A CC wizard? Max Accuracy
A tanky fighter? Max Accuracy
A supporting chanter? Max Accuracy
A DPS Rogue? Min Accu... Of course you'd max Accuracy!
Again, this not to say the current attribute system is perfect, but I'm certain adding accuracy back into the mix would only make things worse.
I may address some of your other points eventually as well, I'll just need to work up to it.
I'm not convinced. +1 Accuracy or +3% Damage and Healing, for example, I'm not convinced that the +1 Accuracy is a no-brainer. And tanks will still want to have defences, maybe even Constitution just for the reduced Recovery Penalty. +Accuracy used to be much more powerful than it is now.
OP, you need to split this up into multiple topics. It's way too hard to discuss all of your points in a single thread because while they are all related to game balance issues, some of them are distinct enough from the others to merit their own threads.
Also, most people won't bother reading your (well-formatted) wall of text. Longer doesn't always mean better, as I discovered when I started posting Let's Plays on YouTube. Despite the quality of your OP, most people won't bother reading it because of its absurd length, not to mention that it discusses a wide variety of loosely related issues.
I tire of regurgitating topics, though, for every Tom, **** and Jerry that falls into the topic 10 pages late to the party and then it's just going to be the same thing over again anyway, I wanted to write exhaustively on the biggest issues as I see them, in the vain hope that someone important would take notice, more than anything else, really.
I agree with OP's appraisal of the current problem, particularly MIG/DEX vs PER/RES with INT uber alles. However, his suggestion is... well, as things stand now, a stat with +Accuracy is just a horrible suggestion, actually worse than INT is now.
Separating melee, ranged, and spell damage doesn't really accomplish anything. If a character is about damage, then they are about damage, so they'll take whichever stat boosts damage. Action speed is actually a slightly different thing, since you don't need to be about DPS to care.
However, separating Accuracy into two different stats would make a huge difference. For example, let's say Accuracy was split into two stats, the first of which now cares strictly about your ability to actually aim and hit things physically with other objects, while the second represents your ability to force your soul on others through effort of will. In general, the first Accuracy would be used exclusively against Deflection, while the second would be used exclusively against the other three defenses; for example, the Fighter's Knock Down would use the first for the primary hit (damage), and the second for the Prone status vs. Fortitude.
As Durance says, names are arbitrary. But let's call my first Accuracy "Accuracy" and the second "Soulpower" (since Will is already taken).
You might have a split like this:
MIGHT: +2 Accuracy with Melee Weapons, +2 Soulpower, +2 Fortitude
CONSTITUTION: +3% Endurance, +3% Health, +2 Concentration, +2 Fortitude
DEXTERITY: +3% Action Speed, +2% Movement Speed, +2 Reflex
PERCEPTION: +2 Accuracy with Ranged Weapons, +2 Interrupt, +2 Reflex
INTELLIGENCE: +5% Area of Effect, +2 Deflection, +2 Will
RESOLVE: +4% Duration of non-Ailment effects you create, +3% Healing received, +2 Will
I feel that's a lot more balanced than what OP proposed.
The problem I see with that is that it would make the Attributes too build-dependant, which is more or less the problem we have right now, and some of those modifiers are far too granular, such as specific to non-Ailment effects. Also, splitting Accuracy up would do absolutely nothing; most characters will already be centred around being either ranged or melee. Non-separated Accuracy would simply mean that you have a flexibility in what you do.
Also, in your suggestion, Might could award a potential +22 Accuracy (!) and Perception +20 Accuracy, a completely insane amount of Accuracy from Attributes. The setup also doesn't take spell accuracy into account. +1 Accuracy is something I think is reasonable, obviously, for a maximum of +10 Accuracy total. And you did not even touch Constitution, which is largely useless as it is already.
I doubt this. Players would just stop killing when the pack is full, go back to sell the loot, then return to the killing spree and collect more. I personally don't see what the angst is about money in these games, as I've yet to see one that actually doesn't have you swimming in gold by the time you're mid to late level. Money, in almost all the CRPGs I can think of that I've played, has only ever been an issue (as in, not enough of it) at low levels.
Limiting how much loot you can carry back would make it less profitable to murder everything, which in turn would give you some incentive to avoid combat.
Going by the IE games, this simply isn't true. You absolutely start passing on chaff loot when it starts to take up space, rather than to neurotically cart it back and forth across multiple loading screens like an OCD cleaning lady. And it's not an angst about money, but about incentives. If you can do something that costs you nothing in any way, but objectively rewards you, you're going to do it. Everyone would.
Meh weapon groups. Just allow to pick any 3 weapons you want/Talent and I think it would be fine. Why would you pick a particular weapon should depend on if that weapon type is actually worth it for particular build or not.
I'm not a fan, I like the flavourful groups, I just wish there were more of them. It just feels like it's connecting me to a concept more, and bridges the mechanics and my character, something I think is important in CRPG:s (although I know many disagree, including Obsidian, if 1.03 is anything to go by, and the changes to the CNPC:s). This is really the reason I want to move the weapons around the groups, too, because I feel that Stiletto is more "Noble" than "Ruffian" and Daggers are more "Ruffian" than "Noble".
Lots of interesting points, I would strongly argue against any stat giving +2 deflection though unless the ability to acquire it elsewhere is severely reduced, you can already make unhittable tanks.
The numbers for Interrupts and Deflection definitely needs playtesting, they're pretty arbitrary on my part. The potential for unhittable tanks is indeed a problem, but I think that's also a problem that they have to take a look at in the core of the game; the situation simply shouldn't happen as par for the course to begin with, it suggests a systemic error, rather than an isolated issue with specifically the Attributes.