You've raised some reasonable concerns that will probably affect other people similarly, I'm looking at a couple of stealth bombers here and they are certainly difficult to pick out the inlays, and difficult to pick which is which but still - my way around that would be to just program both inlays into the door or whatever I was using it on.
As to size, it's a function of the NTAG203 IC, unformatted size is 144 bytes. We are starting to see bigger and better 'standard' NFC ICs though, and there will no doubt be periodic upgrades to the NFC Ring offering. It's a very different proposition to flash memory.
The app is nice, for sure. I've been using it for a while on both my android devices, unlocking with the palm side of my hand - that seems to work fine for me on a number of devices, possibly they're working better with NFC than yours is? Have you tried it on any others? You do need to be reasonably close but I've got a few posts containing videos that show me getting rings to read from a slight distance.
Thanks for the feedback, it all gets noted and listened to by John and the team, as well as the rest of us.