I'd be glad to see some of them for a change too - we've only seen Halloween since I've been here, and it was pretty much the same thing as any little town in the U.S. back home. Not quite Samhain, but it was good old fashioned fun at least. But the wardens definitely do seem to cater to certain demographics more than others, at least from what I've seen, it's true.
Maybe Passover will turn up in a month or two - with this method of time keeping, who knows? Two weeks from Christmas to Easter and no sort of upcoming holiday calender that I've found.
It's hard to tell when the Equinoxes and Solstices are exactly either, since we're only really told when these certain holidays swing by in whatever order they do. Beltaine could've happened across trillions of alternate worlds yesterday in Acumen's calender and I'd have no clue unless it said something. Not sure when May 1st'll come up since for all we know, May 1st could come right after October 31st according to this system.