I think it's interesting in the Dying Earth books* where they only get around 4 spells slots max, should think carefully about which ones to take, and then also think about what equipment they're bringing for helping with the rest.of their adventure.
And so I wonder how it would be in D&D for a class that only had 4 spell slots**, cantrips, and the ability to do rituals from their books.
* We'll, the first three books. In the fourth they're summoners of wackily powerful things.
** Maybe have an exertion track so that in a pinch they could restudy without a long rest, but it would wear them out.