quick swapping to melee will give you the swap buff after a short delay, use this by swapping to/from melee and back right before going into peacemaker, you can get a long duration on the buff as it will reset after a few seconds, giving time for peacemaker damage to ramp up. i use this with Zenurik tree. don't stand still to long in high damage environments, instead bullet jump high before use of 4 to maximise time in the air, you can also use this to move around very freely during peacemaker use, I really don't feel there's any need for waltz.

Peripherals:

I'm using a Rubico prime for this at the moment, the standard viral munitions Bramma is much more lazy.

P: https://overframe.gg/build/133022/rubico-prime/rubico-rivenless/
S: https://overframe.gg/build/133021/aksomati-prime/aks/
M: https://overframe.gg/build/133020/redeemer-prime/blunderbuss-prime/
Regs: https://overframe.gg/build/133018/regulators-prime/strangers-wrath/
Wings: https://overframe.gg/build/133023/itzal/speed-range-itzal/
Arch gun(maybe not the best, built for pure burst damage): https://overframe.gg/build/133024/imperator-vandal/burst-vandal/