What feels inefficient about this to you? The unminified source code is at https://github.com/Fugiman/Twitch-Channel-Status/blob/master/twitch-channel-status.js which shows that the online status of all streams are fetched at once, so it should be fairly efficient.
You can embed chat easily by using an iframe with src="http://www.twitch.tv/CHANNEL_NAME/chat". A follow button is much more complicated.