The game was intended to be more item based than class based. There have been a couple of changes though. You can now use skills much more often and choose which level of skill to use. This makes your class choice a much more active part of combat. Also, for each weapon type, there are about a dozen or so different specials, so even if two magic users are playing together, they can still surprise each other with what they are able to do.
Hope those two changes clear up some of your issues!