I've just been going through the 2010 SCWC (21st century) and noting all the inconsistencies and typos I could find for the compilers with a rapid skim-read. One thing I noted on my way through was how many issues had the obverse/reverse images transposed (even though the descriptions were correct) and, conversely, how many issues that were part of a series had the descriptions of obv/rev incorrect, or at least inconsistent with the descriptions of the rest of the series on the same page!
I've sent through quite a listing of suggested amendments, so it will be interesting to see how many are implemented come publication of the next edition.
As for the debate about which side is which, it's quite clear that there are no completely universal principles, and some issuing authorities/governments clearly decree which is which, and that has to be that. For US coins, the side with the date is generally taken as the obverse; for monarchies, the side with the monarch's effigy or monogram (in that order of precedence, in case they have both on opposite sides!), and for republics, the side with the national emblem or name of the country. I find these are pretty good rules of thumb, though there will of course be exceptions.
I like the idea of keeping the "unchanging side" as the obverse, but again there are cases where that doesn't work (Euros being a current example).
With tradesmen's tokens, the side with the issuer's name is generally the obverse, even if there is a royal effigy on the other side (two reasons: 1. consistency and 2. the tokens aren't issued under royal warrant so the king/queen isn't the (nominal) issuing authority). Same thing goes for countries such as Poland that commemorate former monarchs and other human figures on their republican issues - even though it may feel weird to collectors from monarchies, the "head" side is the reverse in these cases, if the republican emblem is on the other.
When token issuers lacked creativity and put their names on both sides, you just have to run with whoever catalogued them first ...