This is probably impossible, but it would be good to see a system that uses the point based spell system in Unearthed Arcana instead of the basic spellcasting.
For those who haven't read UA, you have points based on level and ability just like you would spell slots, and you use a number of points to cast each spell.
1 for 1st lvl
3 for 2nd
5 for 3rd
and so on increasing by two each level.
Cantips (0lvls) can be cast a total number of times as you have points, but don't use any points.
10 - A Masterpiece, Genuinely Groundbreaking 9 - Outstanding, a Must Have 8 - Excellent, Recommended to Anyone 7 - Very Good, Deserves a Look 6 - Good, Qualified Recommendation 5 - Fair, Solid yet Unremarkable 4 - Some Merit, Requires Improvements 3 - Poor Execution, Potential Unrealized 2 - Very Little Appeal 1 - Not Recommended to Anyone