What is your driver version?

Disabling GPU skinning does nothing. What happens, when starting a game, it starts to load, then goes to windowed mode with the error message popping up to continue or exit,(clicking continue the game just closes after a few seconds). Just tried running the game in windowed mode, and it does finally work, but units have artifacts, which I found goes away if I disable gpu skinning and restart the game.

How does it work with GPU skinning disabled? I guess it might be the same issue as point 2 in this post, except for the driver version — I only know it's older than Adrenalin 24.9.1. By the way, could you test whether you’re experiencing the issue mentioned in point 1 of that post and reply there? Vega GPU users seem to be pretty rare. Thanks!

in my experience, larger maps are stronger for cav because there is more space to exploit the speed difference.

I agree. Melee cavalry needs to be faster than ranged cavalry if its supposed to be a counter. And if ranged cav already falls in that range, thats also good. But it might be better to equalize the speed of all ranged cav to a greater degree (so its not 1.3× to 1.6× but instead maybe 1.3× to 1.4×), then we could reduce the speed of melee cav while still having melee cav quicker than ranged cav (maybe at 1.5× to 1.6×)?   Lastly I wanted to add two more things I think are relevant to the cavalry issue as a whole: For one the entire game is incredibly quick by the numbers; fast queue times, fast build times, fast gather rates. Thus, it feels like cavalry needs to be even faster to keep "the same advantage" as in other, slower rts. Additionally most games are played on "standard mainland settings" or even ambush nomad or pizza, all of which are very small. You can see this by looking at how often people build additional ccs to get more map control (it doesnt happen often, atleast not in my games). Small maps also make cav more effective, since the moment you see them coming, they are basically already in your economy, thus you need to be very quick in reacting to defend sufficiently. 

My first try as the Han dynasty. HanVSPtol_H.zip

I just make the PR https://github.com/JustusAvramenko/delenda_est/pull/70 that enable the summary work again and the game itsel work in current development phase :), let me know