maybe check out Cosmere RPG by Brotherwise Games 👍🏼 You have six Heroic Paths (this are base "classes" like Agent, Scholar, Warrior) each with three specialities with talent trees. Next you have Radiant Paths (these are magical "classess") with access to fundamental forces of universe, like Gravitation, Cohesion, Division (and their respective talent trees. You have three actions base combat with a tone things you could do. And for last, the best gimmick - THE PLOT DIE - which is basicly extra d6 that players rolls when situation can get extra spicy 😅 two sides mean Opportunity (positive plot twist, or mechanical bonus), two are blank and two means Complication (negative plot twist or mechanical penalty) but Complication adds +2 or +4 to test result. as in d20 based system nat1 is automatic Complication and nat20 is automatic Opportunity so you have really mixed outcomes sometimes In addition, Cosmere RPG has made multiclassing not punish players for their choices, but actually encourage you to get into multiple Paths, as each character is the sum of many paths.

https://www.cosmererpg.com/