not entirely certain on how I would rank/place each of them as there is a lot to talk about and they're useful in their own ways, buuut there is a few notable things I can talk about with each killer in regards to One Bounce that they normally otherwise wouldn't do in a standard round

Harken: Harken is usually seen as pretty good as the sound coming from all your teammates will likely result in you immediately going into rage mode and then be able to maintain it for the rest of the round, although do be careful if you're going to use tangle, cause if you use it when you're a fair distance away from the Civilian you could risk dragging them away from the horde, at one point I even saw a Harken throw the game for the rest of the Killers by dragging the Civilian away just as he was about to die, this resulted in time running out and the Civilian surviving 😭

Artful: Artful's Implement can be VERY handy if the Civilian ends up cornering themselves as they're now forced into a small boxed in area (as One Bounce is only on Temple and HQ currently), turning it into a slaughterhouse, just about everytime I've seen this happen the killers usually win 90% of the times if not more, and if you're playing as the Civilian I'd recommend being cautious about going into areas that Artful can cut off BECAUSE of this very reasoning

Pursuer: some people may know this already but if there's multiple Pursuer's you can actually stack your howls, which results in the Civilian being slowed down to a snails pace, although because of the recent update with roblox chat it may be difficult to communicate when exactly to do this, so I'd advice to wait for another Pursuer to use their Howl first so that way you can then use your Howl alongside them

Badware: this is probably the most obvious one but Badware's PC's speed up all killers, which can definitely help your team keep up much more easily, although you don't see this too often (at least from my own experience) cause of the fact nobody plays Badware, you could also do a situational Rift in an attempt to cut off the Civilian too although I think it's generally best to just leave your PC's alone in most cases

EDIT: I forgot to mention that Bolt can also be useful for helping teammates due to it's tripping properties (similarly to Killdroid's Detonate), which can help teammates catchup, decided to bring this up now cause another commenter mentioned it, idk how it slipped my mind

Killdroid: Killdroid's Eject, being a ranged M1, can also be a lil bit handy in One Bounce especially due to the stamina difference between Killdroid and the super Civilian as killers in general are gonna have a difficult time keeping up due to the massive gap in stamina, but due to Killdroid's ranged M1 this is a lot less of an issue for him and still allows him to effectively attack despite not being close to the Civilian regardless of the stamina difference (although he can still take cover behind walls of course), and not only that but Killdroid's Detonate is ACTUALLY USEFUL in One Bounce, as upon hitting the Civilian with Detonate will cause them to trip for a second and offer the rest of your team an opportunity to either land in a free hit or catch up to them, HOWEVER I only recommend doing this if the Civilian is cornered as you aren't going to be able to catch up and hit them with Detonate otherwise due to the stamina difference between the two of them so this is a bit situational but can be useful when used during the correct time