I'd like my inkling to have good fashion sense, but I'd like for her to have abilities that benefit her. For example, things to do with the specials or the ninja swim ability is really useful for her, abilities to do with the sub weapon are not as useful as I hardly ever use it. XD
I care for abilities more. But I've spent 30k ea on some clothes to get them to have three ability slots, sadly I ended up with some abilities that aren't what I wanted. So I'm using clothes that I don't actually love look-wise but got decent abilities rolled.
I've always been the same in games that allow customization. It feels like it defeats the purpose of having customization if I pick my gear based more on the stats they have on them.
Trying to make the gear compliment each other and look good overall, while having ink saver as the main ability for each. And the more sub-abilities the better, though that is obviously not priority since I have stuck to using one star gear for ink saver as their main ability, and since they compliment each other.
Abilities. If something fits well with my play style, then I'll instantly go for it. For instance, I chose a Spattershot because of the Burst Bomb ability, whereas I used the Amiibo-exclusive headgear due to increased speed in ink. Looks are trivial in my opinion.