My current character is 19th.
The highest character I ever had was mid-50's, and have no desire for any of my characters to advance beyond that range. I retire a majority of my character in the mid-30's because they feel complete around then; but some I retire much earlier, and of course many die.
My Redguard, Saiken D'Sei, recently reached level 40 and is pretty much complete. Playing after level 40 gets very repetitive and it's hard to "pick up" a new skill after that, so I generally don't play to higher than about 40. The highest I've got was 47, on my original Argonian.