Feature creep is a double-edged sword. I find it really hard to fault a company (ie a bunch of people) that put so much heart and effort into their games, considering their end-results as a whole. You've got to admire Larian's daring ambition. While some may prefer more conservative, tightly managed development, I suspect that this also stifles innovation, iteration and creativity. I hope that as Larian continues to grow with experience and available resources, they will become better at fulfilling the scope of their visions, better at wielding that sword.
It's also worth mentioning that having only recently cast off the shackles of publishers and gone independent, Larian are still learning how to optimise the publishing side of things. Original Sin wouldn't be as pressed for time had they known not to tie themselves down with certain sales avenues. Regardless of this, I have high hopes that Original Sin may be their most fulfilled and satisfying game yet. Swen did mention that it has the content density throughout that he has always wanted in an RPG.
Besides, this was kind of the whole point of the kickstarter, to give this game the love it deserves, to throw everything at it to fulfil its vision as much as possible. Will I complain if it needs a few patches post-release, so long as I eventually get an awesome epic RPG stuffed full with features, content, polish and little touches? Hell no. Larian's post-release support has always been excellent, and I tend not to play games immediately upon release anyway, as video-games generally only benefit from the inevitable patching.
Back on topic, I highly doubt that Larian would bother doing steam early access, as I don't think they would want the extra hassle while they are feverishly crunching away finishing up Original Sin for release. I could be mistaken, yet it seems that doing early access on steam requires a substantial commitment to the forums there besides an additional technical and procedural burden. Not to mention the other points already raised in this thread. It doesn't seem worth it and I doubt they will want the distraction.
