In MM3-5, the mana cost of the spell Energy Blast increases as the caster's level increases, but it does correspondingly more damage.In any case, even if a spell costs disproportionately more to cast, I still prefer it if it does more damage per casting. You get rid of the opposition more quickly, and your party suffers less damage.
An all-magic party is actually good fun in MM9. If you aim for a final party of lich, mage, cleric and druid, it's actually surprisingly well balanced. The druid is actually the best "half-and-half" character in the game, IMO. He/she is a fairly good spellcaster, and if you max him/her out with GM Unarmed and Dodge, you get a pretty decent melée fighter. The druid's ranged attack is not much, but the cleric can use Everstrike, which is the best bow in the game. Also, a lich armed with Trolleri has a halfway competent ranged attack, because it cam master thrown weapons. (Nothing like as good as the assassin, though.)
I found the two poorest characters in the game were the crusader and the ranger. Both are spectacularly bad. The only weapon where the ranger can gain more than expert ability is GM in bow. OK, it can use any melée weapon, but I'd happily swap that spread of abilities for the capacity to use just one of them well. And its abilities with magic are ok in the early stages of the game, but pitifully inadequate later on. And from what I remember, the crusader is even worse. It's a perfect example of a jack of all trades and (literally) master of none - let alone grandmaster. The paladin's not brilliant, having a weakness in spellcasting similar to the ranger, but at least with GM in armour, cudgel and blade as well as mastery in bow, it's better than competent at physical combat.
