ph0rk
Friendship is Magic, and Magic is Heresy.
One inadvertent result of just sticking with 9 levels of spell casting for most casters is they all have gas tanks of roughly the same size. In a game where resource attrition is both an important part of balance but also buried in the texts and interpreted very differently, this is a net negative.
Bards do all sorts of things - them having fewer overall spells per day would be suitable, especially compared to previous versions. The same goes for Clerics and Druids. The idea that they generally cast as many high level spells as a wizard or sorcerer is strange and not a good reflection of previous editions; if we are to take Crawford at his word on twitter and assume the spell lists are flavor only, if you could use the wizard list on any caster chassis you wished with some reflavoring - why would you play the wizard class?
One advantage of moving to a original-class-casting-slots-only sort of multiclass system is different slot advancement charts for casters. This also then opens up the design room for prepared-slot wizards again.
Spell points for some casters would also make this much more manageable.
Bards do all sorts of things - them having fewer overall spells per day would be suitable, especially compared to previous versions. The same goes for Clerics and Druids. The idea that they generally cast as many high level spells as a wizard or sorcerer is strange and not a good reflection of previous editions; if we are to take Crawford at his word on twitter and assume the spell lists are flavor only, if you could use the wizard list on any caster chassis you wished with some reflavoring - why would you play the wizard class?
One advantage of moving to a original-class-casting-slots-only sort of multiclass system is different slot advancement charts for casters. This also then opens up the design room for prepared-slot wizards again.
Spell points for some casters would also make this much more manageable.