I haven't taken a character past about lvl 35ish - and I've had dooooooooooooooozens. I got about 5 now saved between lvl 20-30 odd. Why? I start becoming uber about then (even on Master) and my enthusiasm wanes a little and I yearn for those haaaaaaard times early game when death was around every bend in the road.
Sooooooo, my latest character - NO PERKS!. NONE, NIL, NADA, SPLAT, SPLAT, SPLAT - all the way I hope to (finally) lvl 50 and beyond.
So far only at lvl 10 and loooooving it. Really mixing up the gameplay as I'm not specialising in anything so from loadout to loadout I can be alternating between Heavy Armour, Two-Handed, Light Armour, Archery, Swords & Board, sometimes pure magic, sometimes I just go out pick-pocketing.
Gonna do the main quest until I get that very special shout at the top of the mountain and grab as many other Shouts as I can, do all the Daedric quests I can, grab as many Dragon Priest Masks I can and try to just stick to Miscelaneous Quests where I can and leave all the rest until I hopefully hit lvl 81 with a completely Perk Free character.
Hoping by the time DLC comes out I'll have a character I can then do multiple saves with and perk or not perk as I wish whatever way I wish and take them on different adventures down different roads. Of course the catch is I can't be specific in leveling Health, Stamina and Magic as I don't know which one I'll end up using the most so I'm just spreading it evenly and the multiple lvl 81 (hopefully) characters will have to live with it.
Something for those to try who've done just about everything else.
Kick your Perks!