Thanks to prior recent discussion and the other thankful and exciting efforts that led to NAND support on the GL-AR750S-Ext - I can now make use of the available 128 MB NAND instead of just the 16 MB NOR. However, referencing https://openwrt.org/docs/techref/flash and https://openwrt.org/docs/techref/flash.layout - it sounds like making use of NOR would still be preferable for as much as possible, as NAND is more easily-stressed, even just for reads.
Previously, I had been following https://openwrt.org/docs/guide-user/additional-software/extroot_configuration to make use of an SD card to successfully augment the otherwise limited storage to allow for additional package configurations, etc.
Would it be possible and make sense to now combine the best of both approaches? Boot from NOR, keep the primary /rom there, etc. - but then use the NAND for the /overlay - and potentially avoid the need for the SD card all-together? (Or at least it can now become hot-swappable again, etc.)
If so, which of the 2 firmware image variations would I want to start with? The "nor" or "nor-nand"? And then how would I mount the one from the other? (I'm guesssing I could figure it out, as I can see the /dev/mtdblock* devices from the nor-nand firmware - but would appreciate any guidance before I start mounting and potentially writing things where I shouldn't and potentially making a mess of things.)
And/or, this doesn't now provide some ability to dual-boot, does it? I.E., to have a primary and a backup firmware - one on the NOR, and the other on the NAND?