Yeah, I find 25 speed is middle of the road for me too. I think like mb 28 is the high end and 22-23 low end. Hitting 22nd orb with 28 speed is pretty rare for me tho.
A few times I've been surprised by how fast you pick up the next 4 orbs. Usually the run dies then b/c I like hit the mushrooms or miss the next trio.
that's actually a bit of an issue in general -- practicing with slow speed is v diff to high-speed. Maybe I could add something to the modded client (I did a little work on it yday)
looking at AC's 1:42 -- https://www.speedrun.com/ssol/run/yj69r8gz
I haven't timed it, but it looks like you loose 1 speed in like 3 frames (at 60fps, too), so that's 1/20 s or 0.05s (50ms). That's pretty fast. max speed is 31.68 (approx 32), so losing all your speed (32 -> 20) takes like 0.6s.
Also, AC hits orb 22 (in his 1:42) at like 23.21 speed -- so mb keeping speed high there isn't so important.
Im happy that you did work on the modded version! Its quite old now and could have some other features. (tho i know it takes a long time and youre quite busy often) For example: making the orb grid thingy open up after starting the game automatically (the thing that you open up by pressing O) And maybe adding a minimap on top right ? Tho that should just be a feature for fun, not an actual feature to use while Speedrunning (since its an unfair avdantage)