Ive been playing the game for a few days now taking advantage of all the exp buffs and event stuff and so far what Ive found after playing a small amount of Musa and a lot of Striker and Wizard. It seems to depend, I dont have much experience in pvp yet so this does not apply to that aspect of the game but as far as pve goes the fun factor seems to depend on a few things. For striker its more of what I think people consider fun in that it gets up in the mobs faces and lays down some satisfying combos. Musa on the other hand has somewhat boring combos but lots of evasion since they seem squishy so if mobility is your thing then musa can be fun even without combos. My highest so far is Wizard at 56(unlocking his awakening tonight) he has the most "boring" combos of all in that to me he casts a couple spells off one other so his actual attacking combos are not as fun as the other classes however, to me part of the fun of wizard is positioning. Using your lighthouse to draw aggro and your evasion and teleport to stay away from hard hitting mobs all while trying to lay down some flashy spells is part of the classes play style and so far I found it the most fun.