Hi there,
I happened to come across the SmartRG SR400ac router. It is compatible with OpenWRT 23.05.3 out of the box, has a UART header inside, though mounting it externally is a challenge if you don't want to make holes in the front panel.
Briefly, it is unusual in the sense that it contains not one, but two flash memory chips, of which OpenWRT only uses one. The smaller one is 32MiB, NOR-type, the other is a 256MiB NAND-type, which appear to be unused by OpenWRT. In the tech data page, I only listed the one that OpenWRT uses.
I filled the tech data to the best of my knowledge and also took some board pictures that I can't upload due to insufficient rights.
Can a wiki admin "connect" the draft page to the TOH?