The achievements gave me something to do. At this point I've gotten every one of them (In 11 days since getting it >.>). I have 200k gold. Explored the majority of the world.I think the only thing I have left are radiant quests.
IMO, If the achievements weren't so easy to get, I would have had more fun. For now I'm just waiting until expansions basically, lol.


Now, some achievements that would have kept me going for a bit longer.

*Beat on Master Difficulty
*Have X hours clocked
*Reach Level 81

Or some stuff along those lines.
Now don't get me wrong, I've enjoyed this game and experienced almost no bugs (I think the only one was game freezes while trying to leave the companion house.) But without anything else to work for it's just...meh.

Why not just play the game and forget about achievements?

Like I said, playing the game for achievements gave me something to work for. I still enjoy it, but playing for nothing is just...bland in my opinion.

Why not just give yourself goals (example: find all locations, alchemy effects, etc.)?

EDIT: Perhaps role play?