This game is nowhere near “powergrinding” since our version got 3x exp rate as its supposed to be.
If you keep many level 10 or above cards expect to grind about 100 hours total during party grind in order to reach max level (anything else is just questing/farming cards) - if you use all level 10 + 11 cards as well you wont have to grind that much at all
100 hours = approx 1 billion exp // you can quest/adventure index/explore to 210 with ease and solo and wont need to grind - if you wanna speed up the 100-210 process invite random people you see on map to your party and convince them on clearing the index…tested on my alt
so grinding 5 hours a day you can reach 210 - 280 in 20 days without using lv 11 cards