What about including 'open up max. number of mmcblk devices' in kernel-plus? I know I know, it would only be helpful if juiceme (ubiboot) and e-yes (nitdroid) would fix their kernels also. And even than nemo/sailfish/other would need to reside on partitions lower p8, but that would offer a lot more of possible partitions/OSes/playground.
I'd say btrf support for example is more urgent atm.
and it worked but setup Opp and run Optimize test said error 'No such file etc'