https://ecasound.seul.org/ecasound/Documentation/
I have not played with kernels, relying on Agent Kith's expertise to recommend some. His own experience suggests that kernels can be hit or miss. Agent Kit is currently building a new infrastructure that will allow us put together our own kernels, but that may be some time away.
Have you tried cpuset which dedicates cpus to music processes? Also worth trying is setting up RAMDisk. Both improved SQ in my INtel NUC setup. A third tweak which I need to re-visit with 20.04 & 1.2.0 is process priority; it made no difference for me in 16.04 & 1.1.n.
Mpd is working fine, but I do not use the MyMpd web player. MAFA is the best Android phone player (but you need to buy it) but you can try the free MpDroid. Soundirok is an iOS player.