It's a great game, but i have to say i am a little disappointed in it as well.
First off, it doesn't have as many quests as in Fallout 3, New Vegas and skyrim.
And those we do get are on average less interesting.
I have about 55 hours on that game so far but i am pretty much done with it.
For a Bethesda game, that's not so much. I have over 100 hours in Fallout 3, new vegas and Skyrim.
Secondly, the game engine isn't that good.
It's really starting to show it's age. It doesn't feel like a 2015 game.
And the graphic to performance ratio is pretty bad. (That's partly the game engines fault)
I am playing GTA 5 on a mix of Very high and ultra at solid 60fps on a 1440p resolution.
Can't do that here. I am playing on high (second highest preset) with the FPS of 50 - 60.
And the game isn't even that detailed to begin with.
Still a good game though.