Downloaded your image last night and (once I erased emmc) had no problems with it booting. As an experiment I took the S950X image available at arch arm and replaced the kernel, modules and boot dir in that image with the files from your build. The resulting Frankenstein image, with arch user space, works with the exception that I get errors like:
[ 915.084822@1] systemd-tmpfile: syscall 278
[ 915.084851@1] Code: aa0503e4 aa0603e5 aa0703e6 d4000001 (b13ffc1f)
[ 915.090014@1] CPU: 1 PID: 3385 Comm: systemd-tmpfile Not tainted 3.14.29 #1
which seems to be a problem with the aarch64 getrandom syscall. I suspect that the arch arm source with the correct board file (I know x86 linux builds well - not familiar with aarch64/arm yet) and config and, if required khadas firmware blobs, would probably fix this. The arch kernel is at 3.14.79.
I have not tested wifi or bluetooth. Network & usb seem okay. For now its still running from SD. The other issue is that arch expects an initrd so when the boot ends / is ro - but a simple remount fixes that…
Any pointers on where I can find an arm guide for people who know x86 well?