Hello Mounerje and welcome.
Well, eric and me are working hard on the 66-tools integration into obarun-install software. Please be patient.
Migration to 66 tools requires a lot of attention, in-depth tests to offer you the best. Things should be available in a short time.
66 tools are really awesome and you have the possibility to move on 66 tools from olders obarun S6 softwares following with attention the thread
Announcements» 66 tools - update: post # 93.
If you have some hesitation to take the step, be patient, everything will be available and integrated soon into obarun-install.
About rtkit, the last release 0.12 has seen changes into the code, and now depends on systemd. After some discussion, it is likely that this will change, but nothing official. That mean for the moment we decided to rebuild pulseaudio and pipewire without rtkit. It's not a problem if you don't use your machine for audio production with audio softwares like Ardour or Pianoteq, for example.
On my side I never used rtkit with pulseaudio for normal use. But if you really need an operating system with realtime possibility, use jack-audio with a fully preemptive kernel, the linux-rt kernel. The various tests that I have done on this subject have proved to me that linux-rt kernel with a fully preemptive process and jack-audio are needed to get the best result for an audio workstation.