Need hlep with pixel size

So i made a pixel art weapons assets it's my first time so i didn't really pay attention to the pixel size.. which turned out to be kinda too big and high detailed for example shotgun is 160×65 it has some extra parts tho to make it looks more si fi and stronger, greand launcher 137×56, lmg 179×63 and have much more but...

my question is should i redraw all the weapons again with smaller size in mind. Or can i upload them the way they are and if not what size would be the best for si fi weapons with extra parts and hige detailed