Brent & Smokey
Thank you for your insights. The biggest driver for our layout was the inverted oil system, that eats up space firewall forward and adds complexity. I have to admit that. Whether it is worth the efforts? I don't know yet. I can probably tell in a few years. We just like the thought that the engine gets enough lubrication even with sustained negative g's. ..and we do that already with other aircrafts (aerobatic gliders, Bückers etc.)
We have not planned to use a more modern battery than the PC680 yet. But this is still an option for the future, as it will be smaller and lighter.
We even consider to add a smaller glove box on top of the tunnel behind the firewall. But it should be removable rather quick bor battery maintenance.
We already have the rear seat footwells