Twitch App doesn't have extensions implemented (yet). Find a way for these users to be able to request songs. Consider old school chat commands for this.
Currently broadcasters are also restricted to putting in requests by the same rate limit users are. Need to add a means for broadcasters (and potentially mods?) to bypass this.
Allow the broadcaster to customize their current request widget by either allowing for manual CSS input or some prefab options. Will most likely be similar to how Stream Labs implements their alert widget.
Prevent the same user from submitting/spamming multiple requests by only allowing one request every X minutes. Minutes can be configured by the broadcaster.
Allow broadcasters to import their library from a given YouTube channel via the YouTube API. Also be able to blacklist videos from their YouTube library so they don't show up as requestable (in the case of announcement videos and such).