I played 1.1 and watched 1.0 playthrough. They're hardly TOTALLY different. Main difference is that some enemies can be defeated (you don't need to sneak past them, but I should say that sneaking is mostly easier and quicker) and there's one forced duel where you need to duel a haunt for a minute straight in the original, but in 1.1 he dies a bit quicker. Everything else is nearly the same, just a bit more palpable.
It's up to you, of course, to keep these releases separate.