[brookish]

I have had really good luck with these boards. http://nanopi.io/nanopi-neo-air.html

$20 but they do not need a permanent SD card and they need a heat sink. The Allwinner CPU's seem to get much hotter than the Raspi Broadcoms. The issues I have experienced really have been nuances of the Linux distros but very workable.

[bedros]

they look great, do they have usable I2C, GPIO libs with support for python of I'm assuming they support some version of ubuntu/debian