[Gimli]

No one has the same magic the Bishop has, ie, the ability to cast from all four books. And no other class gains mage spells as quickly as the mage, plus the mage gets +25% in that school. The hybrid classes get spells more slowly and don't get any bonus to the realm they cast from, and are much harder to develop as powerful casters and melee fighters; almost impossible without using training techniques or having a really small party. I also like melee heavy parties, but I would always have a bishop (or two) around, and a priest is a great melee party "battery" and support character (by the time I was in my final party I had decided I liked having a pure priest around more than a bard or gadgy, and I hated them at first, thought they were so weak). But you can certainly succeed with no pure casters, to each his own - it makes the early stages of the game alot harder though for sure.