one thing,it is for sure more fun to be a vampire in mw with mods.Or evil character,necromancer and such.In oblivions favour there is some very nice vamp stuff there too,but overall mw wins easy.
only thing I can think of,animations is more fun in oblivion,the rest is covered with mods in mw.
and of course it is less handholding in mw,you can actually die very quickly,over and over again,and eventually you learn
maybe a little frustrating at first,but that is part of the fun
so sure,give it a try,and when you are ready to give up,give it another try,it kind of grows on you,it did for me at least.