Simple Keyboard is an actively developed, open source fork of the AOSP Keyboard for those looking for a less bloated, more responsive, basic keyboard with minimal permissions : r/Android
KEYBOARD][4.0+] NextApp Keyboard: AOSP-derived Keyboard with Arrow, Function Keys | XDA Forums
How do I add a number row to AOSP keyboard? : r/LineageOS
Guide] Install LineageOS/AOSP keyboard on any phone | Page 2 | XDA Forums
Top 7 Ways to Fix Android Keyboard (AOSP) Has Stopped