There's a easy fix to stop the MicroSD card from going in sleep mode every time. You just have to change the value from a registry key.
Go to Search Windows and type regedit. Start regedit and go to "Computer\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Power". Right click on CsEnabled and click on Modify... Change Value data from 1 to 0 and click OK.
That's it. Now every power plan is back available and it's possible to make the change to never turn off the Hard disk. It won't make the MicroSD card read/write speed faster but it does seem to fix the annoying delays after being idle for some time.