Don't bother with RT kernel...most of the stuff has been folded into the vanilla kernel at this point. I believe there are enough tweaks in the low-latency to justify its use. There's one user I came across who tested all the various tweaks system-wide and the only thing that made a tangible difference was specifically changing to the liquorix kernel. I've been doing the same thing for a couple of years at this point. Zero x-runs can't be a bad thing
I built my system in 2012 (FX6300 cpu) and these results are with a humble UMC204HD. My usage isn't hundreds of tracks and plugins but still...