9.2.2 itself had a handful of improvements over 9.1/9.2.1 - some of them were in Classic Mode, I think there was something for iPod support, and then there was stability/performance improvements for, perhaps somewhat ironically, a few late-stage applications that, themselves ran much better under OS X anyway. (Final Cut and DVD Studio Pro in particular.) I believe AppleShare IP had a few improvements as well, both in general and if you also installed the newest AppleShare IP 6.3.3 update.
Back in the early 2000s there were a couple people extremely enthusiastic about running 9.2.0/1/2 on pre-G3 machines, both with and without G3 upgrades, mostly for that software. It "makes sense" for the time even though 9.2.2 doesn't really have any security content over previous versions of 9, but if you were, say, buying a new iPod but didn't want to replace an S900 you'd bought new-old-stock back in 2001, I can see why updating to 9.2.2 would've been compelling.
So, today the main reasons to run 9.2.2 is if you have one of those applications/peripherals and want to use OS 9 instead of OS X for whatever reason, if using Classic Mode is important to your workflows and/or you want to run Classic software on newer machines.
For my part, the easy access to the eMac'03 CD, completionism tendencies, and having a few machines that require 9.2.2 (TiBook/1000 and QS'02 in particular) are most of why I have it/bother with it, and the eMac CD's willingness to work on any other G3+ is why it ended up installed on basically everything I run.
For this use case, yeah, I'd say pop a retail 9.0.x/9.1/9.2.1 CD in and see if that makes things any better.