Not only for loyalty, this is very helpful for moderation, so you can see who is in the channel, especially which mods are online or not. The mods are also on the undocumented endpoint.

This would be a great feature for a moderator portal especially for extensions. I want to have a user login, the be able to do edits based on what channels they are a moderator of.

For overlays, goal bars, counters, etc. The data from the streamer dashboard, would be a huge help in Helix. The dashboard endpoint returns the following JSON.

{
"count":1,
"score":1,
"count_breakdown":[{"plan":"1000","count":1},{"plan":"2000","count":0},{"plan":"3000","count":0}],
"score_breakdown":[{"plan":"1000","score":1},{"plan":"2000","score":0},{"plan":"3000","score":0}],
"next_level":{"minimum_score":15,"emoticon_limit":2}
}

This also doesn't even work at all on iOS.

If you compare it to an app store, you have a standard model of leaving reviews, any anyone that downloads an app can leave a review. A lot of apps can prompt to leave a review with an API call, similar to the prompting we have to authorize the app, so they could give a helper function to send a popup to the user in the extension to leave a review if they didn't get on the current version type of deal too, so its a standard flow on any extension