Originally Posted by Sir_Brennus
That's an easy one:
Abandoned Places 2 - Not radically different, but drastically improved. Shame it never was ported to DOS.
Ambermoon - (sequel to Amberstar) Better grafics, better GUI, better story. Shame the DOS port never was released.
Weired Wars - (sequel to Another War) still not great, but vastly improved
Ancient Evil - (sequel to Trial by Magic) better grafics and streamlined GUI
Baldur's Gate 2 - as mentioned before
Bard's Tale 3 - best of the series (the PC version sucked, though)
Daggerfall - (sequel to Arena) bigger, better, more bug free
Demon's Winter - (sequel to Shard of Spring) better story, better quests
Diablo 2 - even if not as much better as most people say, it very much more diversive
Dungeon Siege 2 - now comes including a GAME!
Eye of the Beholder 2 - better GUI, better grafics and END SEQUENCE!!!
Ishar 3 - I think it sucks, but is considered the best game of the Arborea saga
Megatraveller 2 - less complicated, less ugly
Might & Magic V - peak of the old series
Might & Magic VII - peak of the new series
Phantasie III - even improved over pt. 2 that never surfaced for the PC
Rage of Mages 2 - nearly idential, but more diversive.
Questron 2 - does it count, if the prequel was not released on PC?
Pools of Darkness - not better than Pool of Radiance, but better than the rest of the series
System Shock 2 - very different from pt. 1, but considered to be superior
Ultima 7 - tops everything from the first to trilogies
Windwalker - (sequel to Moebius) a little bit more polish
Wizardry 7 - speaks for itself
I am unsure about Wiz8 and the Realms of Arkanias.