hmz well u search for games like Fable (offline) or other games with a great variety of possible options...
sry but i dont know any mmprog (neither f2p nor p2p) wich complies to ur criteria :D
in almost every mmporg u have to do the same thing: grinding ^_^
just a little amount of games let u the freedom to do another things.
For playing in between i would suggest Rakion/Gunz
Here u can fight against each one without spending hours of creating a new char xD
if u want to play a bit longer and with better graphic-engine i would suggest Silkroad/L2
Here u can kill mobs, gather items and do other things which is quite similar to other mmporgs.
But here u have a avaragly kind community who join with u exploring the game-world :D
im waiting for an uber-mmporg like u do, but don't let u be deceived in the dream of playing such uber-game, i dont think that such a game will released ;)
regards,
animus