satori01 said:
MAB is the easiest way to go, to make no PrC based Multi-classing work, and only if in addition to determining Caster level, it also determined what level spells you could cast. Increasing Caster Level w/o allowing higher level spells is like increasing BAB w/o iterative attacks, in fact it is worse than that.
Now this is the most interesting idea that I've seen in a long time.
You don't even have to go to using a MAB, just give classes an effective caster level e.g.:
= level for full casters (wizard/sorcerer/cleric/druid)
= 3/4 level for 6 spell level casters (bard)
= 1/2 level for 4 spell level casters (ranger, paladin, assassin)
= 1/4 level for noncasters (fighter, barbarian, rogue, monk)
and THEN (this is the key bit), grant spells known according to *caster level* rather than class level.
Problems: a cleric 10/wiz10 would whoop ass.
Potential Solution: thus in a D&D world with separate arcane and divine spell lists, give them an arcane caster level and a divine caster level which don't stack. Paladins would give 1/2 level towards divine caster level but only 1/4 level towards arcane caster level; vice versa for Assassins. Perhaps not such an issue in an Arcana Evolved sort of world with only one spell list and type of magic?
BUT - Problem: multiclassers outshine single classes
Solution: OK, perhaps every multiclass has a primary casting focus (divine/arcane) and then you add +1/2 other levels as 'nonassociated' caster levels regardless of your class.
Thus a ftr10/wiz10 would be caster level 15 and have access to 8th level spells, a ftr3/wiz3 would be caster level 4.5 (=4?), a ftr2/Wiz4 would be caster level 5 with access to 3rd level spells. A Ftr4/Wiz2 would be caster level 4 with access to 2nd level spells. A Cleric 8/Wiz 8 would be caster level 12 and have access to 6th level wizard and cleric spells. A Ftr10/Sor10 would be caster level 15 and only have access to 7th level spells, but would get a heck of a lot of them. A Ftr9/Wiz1 would be caster level 5, so his magic missiles are better than a 1st level wizards, but not by much.
Y'know, I quite like this final idea. In fact I quite like this idea a lot. I think I'll discuss it with my gaming group and see if they would like to try it out in my Eberron campaign.