i guess it depends on what weapons you use, really.
run speed up is useless if you use chargers like me, because your running speed is usually really slow while you're charging your weapon up, especially if you use any of the e-litres. if you do use chargers, then swim speed up would be better to have imo, as it can improve your chances of getting away without getting splatted if somebody gets too close. it's even more useful if you use any of the chargers that have the kraken as a special ability, because then it can help you catch up to other people to splat them while you're using it.
i think rsu would probably be more useful if you use any of the rollers because then it'd help you ink the ground quicker. but i don't use any of the rollers, so i'm not sure.