Just use the standard navigation bar
Anti_Weeb_Penguin
I don't think you can brick the FP4 that easily, just be careful with TWRP backups, they don't work well with dynamic partitions.
I use the default Gmail client but i highly recommend K9-Mail.
The nexus 7 2013 supports LineageOS 20 which is android 13
The first android device i ever used was a tablet with android 4.0.4, mfs never updated it and there are no ROMs available for it...
I used it on my Galaxy S duos, I remember installing a ROM called cosmic ROM, it was amazing, but it really sucked for web browsing.
The battery is a fake galaxy s3 mini battery that sadly doesn't work anymore
I have a Galaxy S duos with PAC ROM 4.4.4 intalled, I don't use it anymore tho
I use mine at 90HZ and i can clearly see the difference
I'm using Evolution X because MIUI just sucks and my phone won't be updated to android 13 anyway. The drawbacks are banking apps of course and the fact that i could lose my internal storage data if i forget to flash disable forced encryption.
AOSP keyboard or Gboard if i'm using a pixel based ROM
No custom ROMs = bad phone.