I loved my 7800XT but the ONE game I was playing constantly at the time, Classic WoW, would randomly black screen at least once a session. No other game had issues, just that one. I'd say the 7800XT would be pretty good buy.
5800X3D processor all day as well. You can find it on sale for around $300. B550 board is completely fine for what you'd play. The X*70 boards are overkill, unless you plan to push overclocking and keep it stable at extreme speeds.
I've had my MSI B550-A Pro for a couple years, now with a 5800X3D also with zero issues. I just set the built in XMP/PBO and off it goes. There's some tweaks you can do specifically for the X3D chips to make them run much cooler and still got the same performance. As usual, reddit posts explaining what everything does and how to set the settings.