In my second playthrough I discovered a lot of stuff I overlooked the first time, like the area under the Miller's house and the location of the Doctor who cures Eugene/Clyde, the quest involving Sir Robin, Bellegar's "moral choices" cave, and a lot more. I also accidentally killed the chicken that NPC in Broken Valley got soul-forged with, which was kind of funny.I checked a few walkthroughs just to make sure I'd picked up all the quests, but there are a few things the walkthroughs don't include as quests, like the 3 sleepers. I also found that there are areas you can swim to around Sentinel Island and gather a lot of loot if you can deal with the wyverns.

But I see from some of the responses here that there may still be a few things I missed, so all the more reason to do another playthrough sometime. I don't think anyone can really say they've done it all, achievements or not, who hasn't actually played it quite a few times because how would you know ? It isn't all contained in the walkthroughs or in lists of achievements.

But mostly I think it's a difference of approach. It isn't supposed to be a competitive kind of game with online leadaerboards for best speed run through Orobas Fjords. On hard difficulty I got slowed down a lot by a few annoying boss fights, like Raze, and also because I experimented with my character. The only skill I increased past five was fireball and I only increased that to ten. And none of my weapons did more than around 350 damage. I felt that the game was not tactical enough in a lot of ways which seemed unusual for the kind of game it is, and there are other balance issues. So I made changes to make the combat more tactically challenging and tried to make my character more versatile to see if the game would support that, and it does, and that really made for some great battles, particularly the final battles in both ED and FoV.

But it all takes a lot longer than if you have level 15 fireball, Magic Missile, etc., and weapons that do great damage and that's how I eventually end up with a little over 100 hours in the base game, by experimenting then going back and making changes if things don't work out. I could still go back to any key point in may last playthrough and make any number of changes, or just start all over again from scratch.

So that's the difference between the two points of view here. There are obvious ways you can beat it fairly quickly, but I see it more as an interesting system that you can play around with and experiment with a lot and get a very different experience every time. It's up to the individual how he/she wants to play it. I don't really care about achivements, I'm more interested in exploring the overall design of the game, and what that tells me about the mindset of the people who made it.