I learned the hard way that I shouldn't necessarily cover the whole base all the time (be it from my team or not).
If you leave some empty space unpainted on your base, you can use that area if you get splatted and recharge your special attack quickly enough without too worrying too much on the chaos, provided your opponent is nowhere near to your base.
It's also kind of idiotic to ink in the least busy areas around your opponent's base, since they can easily paint them back and have their special attack ready faster.