I haven't played the game at all yet, so I can't contribute much about the specifics of the points raised but I found this thread really interesting.
The OP reads like a pretty fair and thought-provoking critique of the game. I hope Larian duly considers it. If I was to criticise the critique in turn I would suggest it seems a bit one-sided. That is, a little too much like 'I love Baldur's Gate 2 and want RPGs to be more like it, without addressing the comparative strengths of D:OS except as a side-note in passing. I appreciate that it was noted as a personal assessment and this in no way detracts from the points made, however if the aim is to consider what would make an ultimate RPG by comparison with BG2 I think we should address/debate the strengths and weaknesses of both games.
It's worth mentioning that some people think the Baldur's Gate games are pretty poor and can make substantive arguments detailing why they feel that way. I'm not arguing for relativism here, merely noting that some subjectivity is inevitable in game design discussion. Personally, I love BG2, even if I'm not sure how much I would want Larian's future games to emulate it.
I also think it's worth mentioning that Original Sin was never intended to be the big one and indeed, its initial more modest scope was greatly expanded by the kickstarter so a lot has been designed on-the-fly. I think the amount of iteration and creativity that has gone into D:OS will have been a tremendous learning experience for Larian, indeed a very valuable and important step on the road to RPG nirvana ;-)
I do wonder what Larian's vision of an 'ultimate RPG' looks like.
I mean cRPGs are so diversely feature rich that the vision will be markedly different for everybody. I could certainly agree with a vision that includes a party (six is good) in a richly lore-filled world with a deep tactical combat system and plenty of reactivity, choice & consequence, exploration and world interactivity. Not asking for much I know. Where we go from there is where things start to get tricky.
1)
Combat Having not played I can't really comment except to agree that transparency and documentation of the ruleset makes for a better experience. I would also love a game to have the depth and variety of BG2's spell casting, however I'm open to it being very different systemically. I don't think that cooldowns are fundamentally flawed in themselves, however I do think that any system that relies on them will stunt its tactical depth. I also enjoy the additional tactical layer of resource management that the Vancian casting system (spell use limited by memorisation at rest) provides, and would encourage Larian to consider, not using the system itself but, the benefits it brings to a gaming experience and how those benefits could be implemented in their own games.
About the saving thing dare I even suggest a toggle? I agree it's better to not be able to save in combat in that it makes for a more vital and dramatic experience if there is not even the possibility of save-scumming your way through it. XCOM ironman is the only way to play that game ;-) Yet there is something to be said for giving people choice in their own game. If people choose to exploit the option then they are only cheating themselves.
2)
Roleplaying & Decision MakingI'm disappointed to hear that Larian may have come up short here though perhaps I shouldn't be surprised given the complexity and overall ambition of this game, its relatively modest budget and the degree of iteration involved. The dual dialogue system is just so brimming with possibilities for reactivity and C&C that I hope Larian will one day be able to fulfil its potential. Obviously I'd prefer mechanical reactivity but I'll take illusion and flavour over nothing. I enjoy using my imagination in cRPGs to go beyond what is mechanically accounted for anyway.
3)
Story, Quests, Presentation & LoreThat's one of the main things I've found wanting in Larian's games to date, a lack of serious lore and world-building. I appreciate that there is probably a trade-off with the freedom of their games (for both the player and in terms of design) yet I still feel an RPG won't reach its zenith without a profound world. Of course, what Larian probably really needs is to be able to afford more staff and writers. I'm pretty damn impressed with what they have been able to achieve so far with a relatively small team. I mean think about it, here we are hoping for them to one day produce this amazing RPG. It should seem like a pipedream yet I actually believe they can do it.
I am taken aback however to learn that there are no lore books or unique items in the beta. I can only hope there is a reason for this, eg to minimise spoilers and save stuff for the release, as I was expecting this sort of stuff to be in the game, especially in an RPG that features such awesome item interactivity and discovery.
4)
Graphics, Sound & Design I happen to love the more realistic fantasy look of the Infinity Engine games (and Pillars of Eternity looks absolutely gorgeous) however I'm really glad that not all games look like that.
From what I've seen of D:OS it is looking truly beautiful now and very charming. To my eye it just 'fits' the style of game it is (how's that for a vague and subjective assertion) Actually, D:OS has made me much more open to the potential merits of 3D for 'traditional-style' cRPGs. Incidentally, to provide a contrary perspective, I found the 'slices' of the world in BG2 to be a bit dissonant and disjointed. I mean, I thought Athkatla was really well done and all, but had hoped that such 2D cities could be done better. The interlinking areas didn't seem especially organic to me and required a different kind of willing suspension of disbelief than continuous 3D games.
Variety is the spice of life (so long as we always have 2D-painted ones
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Leaving the topic of D:OS and BG2 aside, my own wishes for an ultimate Larian RPG include:
1) Developing and building on this fantastic new dialogue system to provide greater reactivity and C&C. The entire party discussing things and at pivotal moments of the adventure? I can hardly imagine how complex that would be to create yet oh my god if it could be accomplished...
2) Developing an even richer combat and magic system. More, I always want more...
3) Retaining the wonderful humour, whimsy and player freedom, yet somehow combining this with a more serious and engaging overarching story and world. So far for me the story and lore of Larian's games have been fun, but haven't really made me care about Rivellon. It's more just a fun, magical wonderland to play in than a believable world that enchants me, transporting me into that fantasy.
4) The awesome world/item interactivity apparently in D:OS.
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There are no toilets in D:OS? Immersion broken!
*Edited to fix formatting translation errors. 
