i don't know what's possible, but i'll throw out some things.
if you type alot, the text box on the beta can irreversibly get bigger and bigger. it'd be nice if there was a way to reverse that without reloading.
edit: also if you stay in a chat for a while the chatbox goes glitchy. i don't know if that's due to extreme chat history length? if so, perhaps it could be limited in some way? or maybe my browser isn't accommodating this kind of data.
i noticed that this script stores data to tampermonkey. does that mean chat logging is possible?