These three negatives are the largest turn off for me. Especially the MediaTek CPU. It makes installing roms and updates a nightmare from personal experience. Definitely not going switch because of just a bit better screen and speaker.
AOSP roms will come soon for F2 Pro/K30 Pro, thanks to the release of Mi 10 Ultra kernel source. About K30 Ultra with Mediatek chipset, unless there are engineering firmware used to avoid hardbrick somehow surfaces like with Redmi Note 8 Pro, custom rom development will be hard to take off.