[noggin]

Some Android boxes have hardware deinterlacing (or have it enabled) others require software deinterlacing (which is quite CPU hungry for HD in any quality). Some hardware deinterlacing approaches seem to have problems with some flavours of MPEG2. Pi 2 and Pi 3 (and x86 boxes with halfway decent GPUs like the Chromebox) handle most stuff (Intel has issues with interlaced VC-1)

Yep- it works perfectly on my Pi's- but then I need another box for Netflix/Amazon Prime. It would just be nice to have one box that actually does it all.

The Wetek Core will do it but you are still just dual booting (at least as far as I understand it).

No - the Core deinterlaces fine in Android - no need to dual boot into OpenElec.

Only caveat is that DVD MPEG2 native interlaced content doesn't get play properly. (Live/Recorded TV MPEG2 is fine)

Does the FireTV simply lack hardware deinterlacing or is it just not enabled in their Android build?

Afraid I don't know - but AIUI the Fire TV Kodi builds use a software Bob.