Similar to this proposed change for Pop_OS, just they were defaulting to BFQ for all drives, and want to switch SSDs to a better one, meanwhile Solus uses MQ-Deadline and it would be great to use BFQ for slower drives.
I proposed this change 3 years ago while I was still using Solus on a laptop with a super slow eMMC drive, and changing to BFQ brought massive improvements to responsiveness of the system. BFQ also from benchmarks and user responses improves responsiveness. Pop also wants to change SSDs to Kyber, but not all benchmarks actually confirm it is faster, so probably it is not necessary to change from MQ-Deadline.
Could it be considered again to change scheduler for hard drives and eMMC devices (like SD cards)? All it needs is an udev rule with contents:
# BFQ is recommended for slow storage such as rotational block devices and SD cards.
ACTION=="add|change", SUBSYSTEM=="block", ATTR{queue/rotational}=="1", ATTR{queue/scheduler}="bfq"
ACTION=="add|change", SUBSYSTEM=="block", KERNEL=="mmcblk?", ATTR{queue/scheduler}="bfq"