Terry, do you only use RedSea instead of FAT because you're afraid of a lawsuit?
I'm pretty sure there's no chance of that happening if you just don't sell TempleOS. There's tons of open-source projects that use FAT and they've never had a problem because of it, namely FreeDOS and ReactOS (ReactOS especially, they're super anal about legal stuff). Linux also has drivers for it, that's never had a problem either. I'm pretty sure that whole lawsuit thing was because a company was selling a product with FAT in it, without a license.
Even then, have you ever just thought of making a new type of filesystem that's less restricted than RedSea? The flat filesystem design sounds very debilitating, if I can be so bold.