That is short compared to Fallout 3, Oblivion & Morrowind. I guess Bethesda's the place to go for longevity...
If people are anything like me I kept re-rolling characters to use different abilities (eg going from Soldier gungho to sniper stealth to "magic and tech" etc etc) then split further into that was good and bad too lol
I think I had made a good 5 characters before I picked one to focus on to max out.