As far as limiting the use of cantrips, can't we just say that casters gain the same number of cantrips as they do first level spells? Can't easily cut the durned things out entirely since they seem pretty baked into the game, from what we've seen.
I'm honestly not sure what people who dislike infinite cantrips would want caster to have in lieu of this ability. So as to not make this change a straight nerf of casters. Use of the 1E spells per day progression chart, perhaps? That would screw with the level by level balance--but of course that would be the point, to make the game more 1E-ish.
When was the last time a wizard was actually nerfed?
P.S: Nobody needs to think about this very long.