So... I love this. I really do.
I love the idea, and my mechanical sympathy is freaking out, all at the same time. I love that you designed this, and made it so well. I also wonder if you have flown a 5" with the gopro mounted like this before...
Just gonna toss this out there for you: when I have flown freestyle in this configuration (lightweight frame, centrally located flight stack, bottom mount battery, gopro up top, attached to the top plate) crashes OFTEN knock the gopro+mount clean off the top of the drone. So much so, that I eventually settled on attaching the mount to the top plate with zip-ties, instead of using my preferred 3-d printed mount (that would mount to the top plate with the frame screws, and tear the screw holes off every few crashes). I think about this and look at your wiring, and imagine the ufl port on your reciever ripping off, and the tiny pads on your SUPER NICE RADIX ripping off, and the air-unit "unit" dangling by the power wires, getting choppidy-chop-chopped up by the props in the tiny moments between the zip-ties breaking, and the motors spinning down, andOMGIMFREAKINGOUT. So there's that. An the cost of your air unit-unit.
Sure I get it, it's none of my buisness what you do with your air unit-unit. All anyone ever even does with these things is hurl them as close to stuff as their nerves will allow, at freeway speeds. In the grand scheme of things this is not "WAAAAAAAY MORE DANGEROUS" than normal use.
...but the whole thing you have made here is so guuuuuuuuud, and I have to not say all this stuff, cause' innappropriate... but it's so guuuuuuuud
Anyway, best of luck. It's awesome now, and maybe you'll never crash it. I'm not sure never crashing it isn't also sad though. I can't imagine building this, then not flying it cause some rando' wrote something about it on rotorbuilds, but if you can, rebuild it so it doesn't destroy your air-unit-unit, and your slick radix.

No?
Ok, try this:
You know how sometimes you see somebody, and their clothes look uncomfortably tight? Like they are telling themselves they'll loose the weight if they just keep squeezing into the old clothes they have outgrown? Like they don't have any friends honest enough to just tell them they need to buy new clothes? That's this quad. You just need to accept that you need a bigger SOMETHING to accommodate that vTx. She thicc. That lil' skinny @ss frame can't HANDLE that kind of thicCC-NUss. Lookin like a school buss wearin yoga pants. You need to stop. You can't be goin out in public dressed like that.