I guess one of the reasons you got worried was my story. I personally think that refusals like mine might happen to cases that look very unusual for Warsaw. A common-law couple living in Russia and then spending months traveling in the EU...that visa officer must been really unprepared for that. So if your case is conventional I wouldn’t worry at all.
Yes, without re-hashing your case (which they handled very poorly), the common-law period being split with travelling is an issue that comes up in Canada, too. Also in much of ex-ussr/former warsaw pact, divorce and marriage are straightforward procedures and few cultural issues with marrying (except for same-sex marriage), so I am guessing they see fewer common-law applications - it's easier to just get married. Also the civil registry systems are pretty similar and translations/notarizations relatively easy and standardized.
Plus I'd guess most Polish support staff at the visa office have enough knowledge of Cyrillic and Russian to make out and understand the basics of most simple docs (and there are staff at the visa office in Moscow that can help when needed, even if that office doesn't handle family sponsorship). [A side note: I provided a few docs that I didn't even translate - nothing critical just support docs, like a bank statement and a real estate deed; never heard any complaint from them about that. Maybe they didn't matter at all because a bit redundant but also possible they were so simple they didn't need translation.]
Again our file was (relatively) 'conventional.' And spouse/kids also had previous TRVs to Canada. VFS service in Russia/most of the region is pretty decent - even though I have some complaints about that, they were manageable. The medical tests were handled competently enough. Warsaw (by IRCC standards) actually mostly responded to emails etc.
The files I recall seeing here - apart from yours - that had serious issues were MUCH more complex like authorization to return to Canada and appeals and things like that.
Also a warning, I don't know about files from central asia or caucasus, and now that Warsaw is picking up files from London visa office (i.e. Pakistan etc) some of these experiences may not be fully relevant. (There have been a fair number of files from Belarus / Baltics etc with no major issues, at least as far as I have seen).
But overall, impression is that Warsaw is far from the worst office.
