curious if existing hardware can be upgraded later. i guess technically it might be feasable but vendors will try to make money and sell new hardware anyway. hoping for open router firmwares...
That would probably be radio firmwares; open router firmware isn't rare (openwrt, dd-wrt, tomato, etc.). And yes, it would be nice to get open radio firmware, though I'm not sure how that would play with FCC certification? I suppose if enough stuff is regulated in hardware it could work.
It requires stronger encryption but assuming your hardware is up to the task it'll work. If you're using OpenWRT recent builds with an up to date hostapd support it.