There's a Node project for downloading everything of a Launch property. But looks like it hasn't been updated for a while. Worth a try if there are a lot of data elements to be downloaded.https://github.com/adobe/reactor-downloader 

Yes it's a good idea. Actually I've seen implementations on set top boxes, smart TVs, etc. If the applications have internet connection you can use data insertion API to collect data:https://github.com/AdobeDocs/analytics-1.4-apis/blob/master/docs/data-insertion-api/index.md  If the applications onl...

Interesting question. I'd start with segments. I don't think calculated metrics can help here.

@Gokul_Agiwal is right, you need to be on an AEP sku to have access to it.