I personally despise recasting buffs every day (esp. If concentration, that's multiple level 2 slots down the drain) reloading, relying on potions/etc, so this is why I say it's annoying, but not undoable. It's much easier having a character that can just do it, all the time, with higher rolls to boot. Just leave them in camp when they're not needed.
The buffs just show up in the dice roll window, so I find recasting them is not that much of a chore. And enhance ability spell makes passing a lot of dialogue checks easier, not only sleight of hand, so it is universally useful.
Maybe if the game rewarded limited resting I'd find a rogue useful as well, but it is the exact opposite. If you rest too little, you miss out on companion interactions, sometimes completely (for example Karlach's romance can bug out because of this).
