[wrxtasy]

The new S905 boxes should do most things on your list other than Full HD 3D, though HD Audio pass-through has yet to be seen on them.

Ahem, 7.1 HD Audio Passthrough works already on the S905 MINIX U1 and I'm assured it will also be on the upcoming AML S905 devices from WeTek such as the Hub when running Android Lollipop. You really need to go and look at the MINIX U1 forum to do some pre-reading of any problems this device has.
No OpenELEC on the U1, but you will get OpenELEC on the upcoming WeTek Hub. However I doubt you will get 7.1 HD Audio passthrough with OpenELEC on the Hub, just the regular 5.1 AC3/DTS passthrough.

Full 1080p / Frame Packed 3D is just a marketing gimmick unless you have a Home Projection theatre system to get the full immersive 3D experience IMHO. A small TV does not do 3D justice, unless you sit really really close. I would certainly not limit my Hardware options just to get Frame Packed 3D.

Very little 10-bit 4K content available at this present point in time (apart from Netflix/Amazon) as well due to copy protections on the new UHD Bluray discs that have yet to be cracked. You cannot even home Rip bought UHD discs.

A Shield will run rings around a MINIX U1, for not that much more cost when spread out over a number of years of ownership, especially if purchased in the cost competitive USA.