Filip, I agree with about 90% of what you said. The most dissapointing thing in regards to SS of late IMO are the cutting of corners. Eggshell/PVC/Poor quality capes (See CR Superman) those are on the manufacturing side, and are no excuse other that SS being cheap. Thats not where I am going with this though.
First, and this is in no way a rant about XM, there are only so many decent factory painters to go around. Especially with the general labor demand in China to begin with, this was already becoming an issue BEFORE SS had any real competition. IMO, they caught SS napping on this one and cornered some of the better factory talent for themselves. Even with their lower ES, they themselves are pumping out A LOT of different characters to maximize their 2 year license. Good on them, and I would do the same thing in their place, but again, it's about the available labor on the finishing side, not the manufacturing.
This is where I think this has creeped into SS prices. They say, we need an A+ factory for the paint on this character, and now the labor for said piece has increased exponentially, because someone else is competing for a spot at the same table. Thats why these price points, again IMO, are taking such odd spikes. Also accounts for the wild swings in finished product, as they are looking for new sources to handle the finishing end. Some have been up to the task (Saruman, Sinestro) Some have been wild misses (Iron Patriot, CR Superman) and some wildly inconsistent (Wonder Woman).
Again, all speculation on my part, but it makes alot of sense. I recall reading more than a year, maybe a year and a half ago how many of the factories were complaining about the rates they got from SS, so I can see how out of necessity with more players in the game than ever before, they have had to bump that up much faster than at any point previously, and it shows on the PO page.