I love all 3 that i played(from morro to sky)
They all have there own best part
I love the customization that is more developed in general in skyrim and the snow environements
Overall in term of main quest Oblivion was the best for me, nicely develop and hook me in most. I also think Skyrim's questline lack compare to morro and oblivion.. The college and companions compared to the fighter and mages guild where not on part.... The thieves where better cause of rebuilding the ratway, and the brotherhood is probably on par with oblivion. But the civil war was pretty dull and personally i wish there would had been a definitive good and bad side, or allow us to simply destroy them both and become hight king ourselves... Cause i may have been a stormcloack...overall i think Ulfric is a power hungry douche bag, and the legion just followed order... so well... I miss the Arena as well, it was awesome.
As for Morro, well it will keep a special touch for me cause it was my first game, loved you could make the armor of your dream totally, you could fly also, and it piss me off that you can't kill everybody in skyrim or oblivion.... sure sure it could screw your quest, but why not have the NPC still have the symbol, you knock them down, but then you can execute them if you want in the end... There not even killable when they become useless.. I loved that in Morro i could kill the crooked hight king.
So the best game for me would be the customization of skyrim in term of armor creating and such, houses, with its more developed gameplay, but with the enchanting of morrowind, and its kill everybody policy, but with quest lines just as good as Oblivion.
Gears of War Legend