Hardkernel has a new NAS: oDroid-HC4 (Funnily, the product isn't even listed on its company site, ATM HardKernel). It is a quad-core system with a 4 GB RAM + dual SATA bay for NAS. Currently, AmeriDroid offer a pre-order. Anyway, I wonder if OpenWRT will support this device in the near future. It certainly is a great competitor to the Rpi4.
Not impossible, but not very likely either. Mainline state for AMLogic SOCs is bad, hardkernel likes to use signed bootloaders, not a very good situation for 3rd party support in general and OpenWrt in particular.