Im on a full intel setup. My friend with a ryzen 3 3200g + rx vega 8 GPU also runs it well. But doesn't work well with NVIDIA, blissos.org mentions poor support. Nvidia doesnt provide open source drivers so we have to rely on open source nouveau driver that has many issues and doesnt perform as well as Nvidia drivers,nouveau doesnt support multiple threads on same Gl context so Android freezes. Your GPU will be locked to lowest clock speeds because Nvidia didnt provide signed firmware. but was a experimental build for Nvidia GPUs shared on the telegram group and discord server of Bliss.
Thank you. I can't recall if I tried this, I think the idea is that "nomodeset" tells the kernel to not try setting the resolution itself, and the vga command specifically picks the resolution to use (some common ones, and more info). Luckily I've gotten past this part of the troubleshooting; your post was a reminder to come back and state my findings.
OpenGapps Project website: https://opengapps.org/ (they still have x86-64 Android 9 installer)
I think that going to BlissOS debug mode and running installer script would work, but you need to make /system writable (extract system.sfs and get system.img, and let BlissOS boot with it) and let mount /system r/w in terminal (press Alt+F1 when you are in GUI mode should get the terminal, and "mount -o rw,remount /system" in it).
It is recommended to backup system.img before you modified something.
P.S. It would not work that run OpenGapps installer script in non-Android environments, because the script runs with binaries existing only in (rooted) Android.
If you want to install it in a simpler way, you can try something like "Gapps Installer". But I would not recommend this way because it would have some privacy issues. Therefore, if you want to use it, you can create another account for that.
Instead, if you want a safer way, you can use "microG uninstaller" and then apply OpenGapps'zip to get it. (Sence Android x86 doesn't come with recovery like TWRP, you need to manual "flash" it. (First, make your /system r/w. Second, extract the OpenGapps zip file in root or somewhere convenient. Third, manually start the installer script. After reboot, it would work.)
If you don't want to do those difficult things, you can just use v10.1 beta versions which already include Gapps.