All about an Aran

Would a higher-than-low-dex build be viable? since they deal damage pretty fast and combos are easier i assume to get higher with lower damage.

Still, the less damage you do is going to be less DPM you do. Killing slower to kill faster doesn't make sense, you're just going to lose damage and burn more pots. Faster kills just means you'll get to sweep the map faster, you should still be able to keep up your combo as long as you have enough speed. Also, more damage means more health drained from enemies
Basically, cap your dex as low as possible and use primarily accuracy and dex equips. Not like it's that hard anymore, either. Blessing, medals, maker, and belts all help cut the cost. Still more expensive, but if you can, go for it. Mine's definitely going to be dexless.
I'm not a damage whore, I just think more damage when possible is an obvious choice.