I'm about to DM a group of friends and I really don't want to scare them away with complicated spellcasting so I thought of making the system easier to understand by using physical beads that are spent when spells are used. Since it's hard to differentiate between 20 different sizes of beads I think it would make things a lot easier to just divide spells into cantrips (no bead used), small spells (small bead), medium spells (medium bead) and large spells (large bead). Seems intuitive. Do you have any tips on which spell levels should be assigned to which size and how I might make the system more balanced?
Right now I'm thinking
Cantrips: Cantrips and 1st level spells
Small: 2nd to 7th level spells
Medium: 8th to 14th level spells
Large: 15th to 20th level spells
Right now I'm thinking
Cantrips: Cantrips and 1st level spells
Small: 2nd to 7th level spells
Medium: 8th to 14th level spells
Large: 15th to 20th level spells