This sounds like a good plan to get newer developers on board. As someone who has overcome some of the hurdles already I would love to see some of the utility of this to be used for those who have their own environments set up. For example I would like to see broadcaster, viewers logged in and off, all on the same screen while it hits my own web server running on local host or hosted at twitch.
Another thing I have had trouble with is the ability to test account features I have not unlocked, such as subscribers, relying on the mercy of friendly streamers to test. An environment which will unlock all features and api calls would be very helpful.
Cheers