Yup i rooted with v21 too.
Anyway I don't feel like going through the whole back to stock fiasco right now so I'm going to test out a few gapps packages and post what works for me. For now NikGApps Omni doesn't have the same problem, but it doesn't have the apps I need. As far as I can say, the problem is caused by the pixel setup wizard or the pixel launcher.
Regarding this,
I have now tested three GApps packages on fresh installs of this ROM (NikGApps, BiTGApps, Unofficial OpenGApps ) and the problem with the gesture navigation bar i had posted before seem to only be present in the Macro, Stock and Full versions of NikGApps.
However, i have noted a few more even annoying issues/bugs.
1. The "Compact" navigation bar option seem to revert back to Normal in a while and i have to change it back to compact again from the "Radioactive Tweaks" for it to be compact again. - The setting however remains at compact, i have to click on normal and then compact again for it to work.
2. I can't seem to get Google Voice Match to work. I have been using this feature in my previous ROM with the same account i use for all my phones, i tried deleting my voice model and retraining it but it just turns back off when i go back to that menu. I assumed this problem has to do with the GApps so i tried this on all three packages i mentioned before, the problem seem to persist in all of them.
3. Thirdly, there is no live wallpaper picker installed with this ROM. I understand this isn't a priority feature, and it doesn't affect anyone's daily usage, but since Android 10 supported it, I'm unsure why it isn't included in this ROM..
[EDIT:] 4. There was also an issue with the MIC with WhatsApp and normal calls. This never happened to me when i was using POSP.
I would imagine these problems are either with this specific ROM or the Android device trees since they seem to be common in all the GApps versions out right now, So my next step before i flash CFW V2 and go back to POSP is to try all these GApps with the two Android 11 ROM out right now (Pixys and if that fails AOSP).
Anyone else have these problems?
[EDIT:] Above problems are also present with Pixys, with the exception of the live wallpaper picker, which is available in that ROM but for some reason crashes. Since these problems will affect my daily use than the touch lag and the memory management issues in POSP, i'm going back to POSP.