Absolute...
Gameplay:
Absolute control as in many RPG. Lots of stuff to learn, lots of skills variable between type and class. Many items to combine is a good step. Existence of normal, exceptional and elite items wich can be simpl, magical, rare, set items and unique with the posibility of beeing soketed or beeing etheral...check blizzards for more details.
Graphic:
Well at this time you won't find graphic so interesting or cool but at that time it was a splendor!
Sound:
Not so much sound. Of course there is the music and dialog but I refer at the SFX wich is not so great.
Choos Diablo!