Highest toon is level 145ish or so. Current playthrough my toon is at level 98 (still haven't started Dawnguard, Elseweyr, Falskaar, the Companions, or the Dark Brotherhood on this playthrough yet).
Hard to say how many hours I put in per toon, usually around 300-500 I would guess. I tend to play until I finish all the main stuff, all the thanes, all the guild quests, all the standard DLC's (Dawnguard and Dragonborn) and at least a few of the extended lands mods I download (Falskaar, Elseweyr, Sanctum of the Fallen, ORS, etc).
And right now I use the Uncapper with skills capped at 1000, (effective skills being 200) though I think I've only hit 200 on a skill once or twice before as I rarely buy skills past the lower levels). I also use the Scalable destruction mod (incinerate hits around 300 per hand right now at around 180 skill). I think my highest skill is 183 or something... I believe that's either destruction or smithing.
I also use Dragon Soul Relinquishment and Dragon Merchant for buyable dragon souls and stuff to buy with dragon souls (hunting Dragons is always useful for me, even after unlocking all shouts).
I also play on Legendary and use a variety of increased difficulty mods like Deadly combat, Dragon combat overhaul, etc. If you're going to hit hard and be strong, you need tough enemies to keep it challenging (and tough mods like Sanctum).