The possibility to embed Streamlabs (and other) alerts when streaming thru the Twitch mobile client.

Embedded like a browser source, I would say 1 or 2 sources maximum (to keep in mind, it is still a mobile thing).

I think this will help to create a better experience on and with mobile, because the look and feel for the viewers - compared to a Desktop stream - is kinda similar and familiar.

Twitch already offers some options to use Streamlab components in Chat, why not extending the good experience in the Broadcast-part, too?

With a simple grid system...

1 - 2 - 3
4 - 5 - 6
7 - 8 - 9

... the Alert layer can be aligned, valid for Portrait and Landscape format of the phone.

I think that will encourage more Broadcasters to do IRL from abroad, because known elements are still used and visible - for the Broadcaster and their Viewers.