As regards this problem with OH2:
I was finally able to solve this issue. I installed openhab on a second Raspberry Pi system because I thought I was going to have to just run multiple instances to cover all my devices. However, on the new installation, I could not reproduce this bug. I was able to get Alexa to see 90+ devices with no problem.
I tried a bunch of other things to repair the first installation, but in the end it was the nuclear approach that worked. From the osgi console, I typed:
smarthome:items clear
smarthome:links clear
I also deleted the contents of the following directories:
/var/lib/openhab2/cache
/var/lib/openhab2/hueemulation
/var/lib/openhab2/mapdb
Note: be careful with these commands! This will delete all of your extensions, your hue emulator pairing data, and your mapdb database! Of course, you can just reinstall your extensions through Paper UI or they will be automatically reinstalled if you have them defined in addons.cfg, but your item state DB will be lost.
I can’t even really recommend this approach since I’m not sure exactly which part solved my problem, but if anyone else has a similar issue at some point, these are just some things you can try.
Oh, one other thing I should mention, I also updated to an OH2 nightly build from beta4. I’m running build 576. I tried updating first though, and that did not solve the problem - only the steps above did, but it’s worth mentioning since perhaps updating does factor in to this process somehow.
(I posted this in the other thread as well, just in case it helps someone)