jackoneill
I really don't want to suggest anything but the code in SVPflow is really cleaned comparing to original MVTools
Just compare a few numbers - as you already know all the magic is in "PlaneOfBlocks" cpp/h, and they're ~80 KB of code(*) in MVTools (and in your build too) BUT only 42 KB in SVPflow.
(*) huge commented blocks are also included
Also original MVTools loosing >= 20% of performance just for nothing...