I found a pretty interesting IO board from a Chinese company called U-Geek;
The only place I found it for sale is on its Aliexpress site, and it has some limited information available on Sourceforge. The board breaks out the IOs in standard RPI header and the remaining bank 1 gpios on that 14-pin header next to it. It also has the HDMI and dsi/csi ports. I think that microusb-port on the left is only for flashing the eMMC on the CM3 (non L) but I'm not sure -- maybe it's what the 3-pin header next to it is for as well? No network or analog audio though.
I find it interesting because of how compact it is, that it has the standard header and HDMI output, but mostly because it seems to come with an integrated battery charge module with an on/off switch for controlled shutdown? So given that it hasn't got the USB/Ethernet chip of the standard Pi, it should be fairly current-shy.
So since they sell the board for $75 shipped which includes a CM3L, I've bought two of them to use in a mobile project or so. Does anyone have any experience with this board, or any insights into using it?
I'll update this thread when I've received the boards and had a chance to try them out.