I have to agree on the contest aspect. Twitch streams, due to a multitude of variables, are really unfair for holding something like 'who says x first in the chat'. Perhaps look into using an IRC client and bot to help pull out and log all correct answers (I know how quickly Twitch chat can get fly by) in x time, removing/disqualifying duplicate answer spam, and select one randomly from that pool of correct answers. This is much more fair to all viewers and less based on who has the best bandwidth. There are also a variety of apps out there for running contests based on who is live watching, who is chatting, etc.

The graphics were a fun touch, maybe look into a soundboard so you can have the related sound effects tied to them for next time (limit filling, limit used, clicking through menus, duty complete, etc).

I also agree with above about interacting with the chat room more. People really feel like part of the discussion and less a spectator when they are acknowledged in live (or delayed live per Twitch).

Perhaps see if you can get the rights for sharing artwork images more clearly from previous Live Letters. I love seeing Yoshi hold up the artwork, but sometimes we can't see all the details too well due to the distance of the camera. If you guys could put up closer, still scans, that might be a nice bonus for folks to see.