In a way, although DoS' MP system is less complicated, it makes things harder, because the original MP system in FFI allowed you to cast all the level 1-7 spells even if you ran out of all the MP for level 8 spells (because casting level 8 spells didn't affect the MP of other spell levels at all). However, in DoS, when you're out of MP, you can't cast any spells anymore... although to counter this, the system in DoS (at least according to what I've seen so far) gives you so much MP that it's very hard to run out of them.