Another one of the big differences is that Master of Magic has city building and development. Sure, it might not seem like a big deal now, when, if you're like me, you've played through as every race several times, but I remember quite well the first time I built that pegasus stable... In Master of Magic, with good planning you can locate a city by an adamantium vein and create an army with which no one can compete!
Originally I played Master of Magic on a 486sx and I also remember quite well the first time I played it on a pentium, watching that same pegasus' head bob up and down at hyper speed......
Heh heh, Dominions also has working multiplayer.
