Looking to upgrade my PC for multiboxing

Old player here looking for some advice on what is needed for running around 8-10 clients at once.

Current Setup:
CPU: Ryzen 7 2700x
Ram: corsair LPX 32 gb 2133mhz ddr4 mem (speed is limited by the cpu so i know to update this)
Graphics Card: Radeon RX 5500 XT
Motherboard: ASRock AM4/X570 Steel Legend
PSU: EVGA 500 W1, 80+ 500W (white version)
CPU cooling: Cooler Master MasterLiquid LC120E 120mm Radiator
6 x 140mm corsair fans (4 x Air Flow , 2 x static pressure)
Monitors: 3 x SAMSUNG 34-Inch SJ55W Ultrawide Gaming Monitor 75Hz Refresh, 3440 x 1440p

I am a team red guy so not into Intel or Nvidia, even if they are slightly better than the Amd/Ati equivalent (tiny differences are only so meaningful especially when cost is in play)

I am looking to fly at least 4 toons with max graphics (potato mode is untenable for me I play for the fun and the visuals). Looking for fairly decent upgrade without breaking the wallet, but still upper mid tier setup ie: can play anything on 4k screens with ultra settings maxed out, if it cant do that I am not interested in the setup if that makes sense, I will splurge if i must.

Thanks for your advice. I am experienced in 3 or 4 toons on potato mode, but want the visuals and more capability (I have 12 accounts total)

Have you looked at ccps recommended specs?

Recommended System Configuration:

OS: Windows 10 64-bit
CPU: Intel i7-7700 or AMD Ryzen 7 1700 @ 3.6 GHz or greater
RAM: 16 GB or higher
Video: NVIDIA Geforce GTX 1060, AMD Radeon RX 580 or better with at least 4 GB VRAM

Yeah thats for playing the game not multiboxing. I am trying to figure out what specs i need for running 6x that or more.