That is a beast

.
Not my cup of e but looks well thought out and executed. Except for the battery placement which you obviously realized and have made adjustments for.
I am curious as to what you have going on in the bb area? Maybe a drive side view would help?
Here is a photo of the drive side. If you are familiar with "Mountain Cycle" and their shockwave downhill bike.
The idea is to get to the top ( the particular downhill ride) then its freefall...lol) The south of France has some fantastic rides, and extreme conditions demand rather extreme bikes, obviously the build hasn't the "ride to work" thought in mind, but the both wheel drive are a serious plus in rough terrain.
This is off road, (as to your "cup of e" ) granted its a narrow spectrum in the ebike world, and even more limited in its downhill function relative to the huge market of this e trend. The work on this build is progressive, each ride brings a modification of some sorts, which is why the battery is being moved to the rear. Otherwise the shockwave is a fantastic frame to build from.