Valid points. Your way of templating does sound like an improvement on the ‘old fixed list of recipes’ approach. I am actually thinking of having all characters capable of a half pound total as a base level, and the casting take 1-3 rounds. In exchange for regular casting ability, the players may choose Uncast with their casting weight–which might mean the whole party will be necessary to cancel a spell. . .of course, using fire is probably unwise, like calling down mortar fire on your own position. Doubtless counter-spells would have been thought of by experienced battle mages: putting out fires or things made of fire would be an interesting problem.
My system is intended for people who want fewer limits on possibilities of magic, like your comments on fantasy races. I only have three interested players at this time, and none of us will have time to play for, likely, another calendar year. (This is the point of testing, though, to make sure it works before then.)