Best bet is:
- wait for NOTE 3
- hope NOTE 3 has the same SoC as Nexus 10 (and somewhat similar kernel)
- wait for interest and support
- someone takes the "know how" on porting Ubuntu from the Chromebook and Nexus 10
- they make an Alpha-stage port of Native Ubuntu running on the NOTE 3
- as time passes, port gets slightly better
- you figure how to iron out some kinks yourself, and manage to install your GUI of choice (Mer/Plasma Active etc)
- done!

Otherwise you could:
- wait for exactly 12.3456789 years for a company to make a FOSS mini tablet

And if worse comes to worse:
- bite me :P