Are you kidding, you can buy a "picture" of a 5090 FE for the low price of $1500 on ebay. Seriously are these guys smoking crack? Sad part is it's not the only one.
Glad to see an AMD card that is really 2 slot. I really wanted to buy a 7900 XT when they launched but I was still using a Ghost and there was nothing available. Ended up going with an Inno3d 4070 Ti and I'm very happy with it but I would have liked to have the option.
Change your CPU/GPU combo.
Check out this video from Hardware Unboxed where they compare a 7600+4070 Ti to a 7800X3D+4070, in almost all gaming except for some esport titles at 1080 the 7600+4070 Ti is a better choice. This video was done before the Super versions released and the 4070 Ti...
Not sure where you saw a 300mm 4080 from Inno3d but there isn't one. Smallest 4080 is 328x137x62mm, there is a dual slot 4080 Super but it is 337x141x40mm.
Edit: Just realized you might mean the Inno3d 5080 which is 300mm and dual slot.
Good luck with your build. I recently transferred my build to the T1 v2.5 mainly due to price and availability over the v2.1. I have heard the v2.1 is of better quality and if that is true it will be truly amazing because my case is really nice.