I implemented the last upload of your Expanded Perk Tree Modlet for EW using UPKModder (including the two files prefixed with double underscores, but not including the gamepad folder files - as found here)
And though it appears to be fully functional and configurable via the DGC (which is great) it displays some UI symptoms of 'entanglement' with LW code (which you did warn about).
Firstly, when browsing Soldiers from within the barracks there's an expanded display window for various attributes with some snazzy icons (note I had previously included the 'Display Mobility and XP in Barracks' modlet in the captured image as I wasn't expecting the EW Expanded Perk modlet to influence this). I really like this use of icons over text for HP, Mobility etc, so I'd either like to make it properly functional by making the 'undefined' values display the correct amounts or simply revert to Vanilla instead. Any help in either case would be sweet (I'll of course remove the redundant 'Display Mobility and XP in Barracks' modlet if the former is doable).
Secondly, and more of a serious issue, when choosing a squad for mission deployment the UI appears provisioned for LW's eight+ Soliders by default and thus Vanilla's initial four-to-six options are quite severely right-shifted on screen. (Note that the fifth and sixth 'slots' are not accessible at all).
Looking over the code it's not clear to me at all what is governing this (it's a my-end issue)
I'm basically recreating my old EU Patch 4 mod for EW and most of the basic rebalance and a host of less complex features are complete.
In the meantime I'll go back to playing current Long War which is truly great and is far better realised (imo) than the versions I was last familiar with a year ago. =)
Fantastic work as always from yourself, Johnny and Ghost.
PS: Aggressively-Psionic-Sectoids is pure gold!