Thanks so much for playing, and for taking the time to write all that out — this kind of feedback is genuinely hard to come by.
You were right about the battle lag, and it turned out to be a real bug on my end. The battle scene was running desktop-level graphics settings in the browser — the shadow map alone was 16× larger than it needed to be, plus anti-aliasing and ambient occlusion on top of it. That's also why the menus felt fine: those screens are pure 2D, so none of it kicks in until a battle actually starts. Exactly matching what you described.
I've cut all of that down for the web build. It should look the same but do a lot less work per frame. If you get a chance to give it another go, I'd really like to know whether it holds up on your machine.
The camera issue you hit is real too — I'm still working out the right fix. In the meantime: the small Trk button in the bottom-left toggles camera-follow. It's on by default, which is why the camera sometimes drifts on its own.
And please do drop the YouTube link — I'd genuinely like to watch it. Watching someone actually play catches things I'd never find on my own.
Thanks again, really glad you enjoyed it.