My thoughts? This is terrible design. It generates numerous unresolvable problems.
-First, it invalidates the decisions you make during character creation. Picking a well balanced party is pointless, because even if you don't take a thief you don't miss anything. So the "decisions" you make during party creation are meaningless, because it ceases to matter what party you make, you'll be just fine with anything.
Are you serious? No really? Are you serious? Did you not pay attention to what Sawyer and the rest of the people were saying? I mean, its like you heard "We're gonna balance things so nobody can just dismiss any class or skill", and somehow got "We're gonna make every character identical". Not to mention, being fine with anything does not mean you'll get to experience everything. Sure, you can beat the game with 6 warriors, but it will be a completely goddamn different experience than playing with a regular balanced party. Nowhere in anything did he even imply that somehow imply that you no longer want a balanced party. Nowhere.
-Second, it promotes degenerate gameplay. Since it doesn't matter what party you have, the only party to have is the one with the highest damage outpout. Right there, the healer class, thief class, bard, ranger, druid, etc, they're all useless. The only characters to make are the Fighter and the Mage. Because all of those special purpose classes no longer have a purpose, since "We don't want any class to be necessary", those special purpose classes are no longer necessary. In a system where you don't need to have a thief to open locks and find traps, there's never a reason to pick one over a fighter. In a system where you don't need a healer to heal you, there's never a reason to pick a Cleric over a Mage. Especially since that also means your class won't open/close any quest doors.
There it is again. Look, being able to solve every encounter with any party layout, does not mean that every party needs to be able to finish it identically. Hell, outside the main quest, it doesn't even mean that specific party layouts can solve it. Not to mention, are you seriously claiming to understand the classes and systems Obsidian is putting in place for clerics and other spell casters? How the hell do you suddenly know what these clerics are gonna be like now that healing is no longer just straight give more people hp. Next, you once again are somehow thinking that not being necssary is now equal to being useless. It's just the idea that yes, I can have my warrior run through those traps, and be severly weakend for the next fight, or I could have my theif go and disable em. Or hell, maybe I'll have my mage summon monsters to "disarm" em, or better yet, I'll mind control my enemies with my Chanter, and make the enemies run straight into their own traps. See, I was able to come up with situations that would be completely different and viable, without relying on any single class.
--Third, it starts closing doors on story. Can't have a storyline involving your Cleric desperately trying to heal someone, they can't. Can't have a storyline about your thief trying to steal something, your thief isn't special anymore, anyone can do it since we don't want to have to require a thief.
I have never, EVER, heard of a game like this that gave you class specific quests. Ever. It has not been done. Period. And hell, you're the roleplayer right? If your reason for ass kicking i to heal every person you see, or lighten the pockets of every merchant you come across, you can still do that. Once again, I really don't get where the hell you're making these assumptions from. Its like you're assuming the developers are all idiots, who can't tell the difference between balanced, and everything being identical. Also, how exactly does allowing for a more diverse style of play close doors? Sure, now they won't suddenly know exactly what the player is capable of in each encounter, but that just means that they will have to allow for even more freedom in how to solve these encounters, not less (Unless they're terrible developers).
Honestly, PE is really starting to reek of 4th edition Dungeons and Dragons. At-will magic powers with cooldowns, no healer required just get your "Second wind", etc. Considering that 4th edition D&D didn't do well at all, I'd really caution against using the systems from it as a design model. Generally speaking, if product A sold badly because of it's qualities. putting them into product B will have the same result.
4E sold well, and has a sizeable fanbase. Its about as popular as Pathfinder, and it is fun, if for different reasons. I don't want PE to be 4E, and I don't want it to be pathfinder, I want it to be PE. And right now, we don't know much about how mechanically these classes will function, and how they will vary. But we do know that Obsidian is pretty damn good at these kinds of games, so at the very least we can give them the benifit of the doubt until they start telling us exactly how the game actually plays, instead of just assuming that what ever design their going for already sucks.