Use AOSP ROM directly from android developers
( not the google re developed )
This rom has 4 biggest advantage
1. No restrictions on update support , as long as you are using this android core developer ROM you are free to get updates for lifetime or till android remain alive
2. You will get both upgarde and downgrade feature
3. Manual choice of pre installed app or just android
4. You have a choice for updates e.g. Daily update , monthly update , quarterly update , critical update and general updates
Main disadvantage
1. Some hardware do not function in its first install , user need to select the correct binary files from update installation menu to have working hardware such as VoLTE , MST etc , which requires more technical knowledge. Example if you dont know what chip samsung do use for VoLTE support than you can't get VoLTE using direct installation, you need to select the exactly the same binary file name in update or installation menu for first time
Here is my test device snapshot where i do use AOSP ROM FROM android.com with working VoLTE and sensors binary , This comes with Just Android and play store and an UI nothing else
( for latest release you need to enable beta option in the update settings, e.g if you want android 10 now , AROMA variant offers manual selection option for which app you want to be pre installed)
Snapshots
