Why is everyone so intent to strap themselves into a glorified skinner box? If you didn't like the late game quests, a serotonin injection into the brain isn't actually going to make them any better. It'll just dope you up, so you don't care if you're having fun.
An early level cap is perfect. It gives the player more leeway on which quests to follow and which to ignore, which is something you should be extra thankful for if you're getting bored once you hit the cap. It also makes it easier for developers to balance late game encounters, which are supposed to be the pinnacle of the game, hence need good balancing (in theory anyway, I don't think Larian has quite figured out the second part yet).