So, things that make the character die easily (like having d4 hit dice), suck to be have around, or make it so the caster frequently has little to do (having to horde spell slots and have no cantrips), are solutions I'd avoid.
Part of it would depend on what specific problem my group sees in the wizard.
Two things that come to mind:
1) Scrutinize my adventure design and use of rests. Yes, that has nothing to do with the class design, but all classes interact with rests, and maybe the issue is that I'm setting things up to be favorable to the Wizard, but not to short-rest classes.
2) Consider restricting not the number, but the types of spells, the wizard can cast - not on the level of the class as a whole, but as an individual. Previous editions had a concept that specializing in a school also meant not being as able with spells in "opposition" schools. Making sure that wizards cannot really be "generalists", or that they must give up other goodies to be so, especially at mid and upper levels, might help solve the problem without much alteration of the rest of the class.
Part of it would depend on what specific problem my group sees in the wizard.
Two things that come to mind:
1) Scrutinize my adventure design and use of rests. Yes, that has nothing to do with the class design, but all classes interact with rests, and maybe the issue is that I'm setting things up to be favorable to the Wizard, but not to short-rest classes.
2) Consider restricting not the number, but the types of spells, the wizard can cast - not on the level of the class as a whole, but as an individual. Previous editions had a concept that specializing in a school also meant not being as able with spells in "opposition" schools. Making sure that wizards cannot really be "generalists", or that they must give up other goodies to be so, especially at mid and upper levels, might help solve the problem without much alteration of the rest of the class.
