Hey there,
I got a few suggestions.
1. Improvements to demo player
Make this demo player be toggleable or automatically hide it after a few seconds. Makes it easier for video editors.
Also let us use hotkeys for the demo player; maybe SPACE for pause/play and +/- for speed-up/slow-down.
2. Add support for secondary hotkeys
Allow as to use several keys for the same action. I know you can use the config file for that, but it'd make it easier to be able to do it through a menu. Lots of games support this nowadays.
3. Change for votes
Because hivemind is strong. Maybe make it configurable by server admins so it can be disabled if not desired.
4. Native support for controllers
This may be a little far-fetched, as I have no idea about the coding site of things, but a few days ago I tried out playing with a controller. I had to use a external tool to get the keybindings working. It worked surprisingly well considering - of course not pro levels of movement, but most definitely was fun. This is probably low priority though, seeing as teeworlds really is meant to be played with KB+Mouse.
greetings,
wappsify
burn the land and boil the sea, you can't take the sky from me.