Could you please take the latest kernel from here for a spin and see if it works for you? The packages are armv7hl but that's not userspace dependent, so it works just fine with armv5tel userspace (you may have to install them with --ignorearch, though).
(TODO: test armv7hl on Chromebook 1, Asus Tinker Board and Genesi Efika Smartbook)
I only tested it with AC100 (Tegra 2) and Chromebook 2 (Exynos 5420), so please let me know if they work for you and if you need any changes to make them work with your hardware.
I have a cron job set up that builds new kernels daily as soon as they are released, so these should get auto-updated regularly (may be a few days late if the updated kernel contains a breaking config change requirement).
There are also aarch64 kernels here, if you would care to take those for a spin and you have aarch64 hardware. Only tested on MP30-AR0 so far.
(TODO: test aarch64 kernel on Raspberry Pi 3)
There are also x86_64 kernels in the predictable path, but that's a bit off-topic. :-)
Any config changes you would like to see in these (e.g. adding a driver, doesn't work on your hardware), let me know.
Finally, if anybody is interested in ZFS packages, let me know and I'll expedite putting them up on the server. I have the latest ZoL 0.8.1 working on all the hardware I have these kernels tested on so far, and it works really well.