They should make a mage tank that’s good into mages. Maybe magic shield on passive, some damage ability for Q, some kind of AoE disruption for W (taunt or something) some kind of engage ability on E (maybe a dash?). And team magic damage shield on R with some CC also.
Fun can not be quantified.
If you have fun, you will be more motivated to play a champ more. The more you play, the more you improve. And then you have a main.