Roguey, leveling can actually make you weaker in skyrim, if you level the wrong things. Sure, some enemies have a minimum level, but thats extremely low either way, compared to the pace at which you level.
For example I kinda laughed at your "stealthy" character, all stealthy characters and using poisons in skyrim do is make you kill faster at the start, which means your armor and weapon skills will level up slower. Not only that, those stealth skillpoints make you grow in level without actually affording much effectiveness in the battlefield, the reduced stealth speed actually makes dungeon crawls take many times the amount of time they should, so in a way you are hurting your progress for absolutely no benefit, its only detrimental to your character.