Well @Rik," this test build" is a /e/ OS ROM.That /e/ Apps Store “runs like a breeze” there is to be expected, right?!
The joke of the matter is that the /e/ components I mentioned work on a LineageOS 16.0 for microG ROM.This allows me to use the “a3xelte” with /e/ OS Feeking including Android security patch level May 5, 2020.
Below is the /e/ Apps Store in action on a LineageOS-16.0-for-microG ROM (in 13 pictures)