<<My wife and I enjoyed many overnight sailing trips on our Ericson...Is the pop top worth holding out until I can find one?>>
If you want to overnight on a Cat 22, my personal opinion is that you should hold out for the New Design ('86 and later). You also get a usable galley. Many of the older boats have a removable "slide-out" galley that receives little but ridicule regarding its practicality. The new design has a built-in sink with a remote 5-gallon water supply available through a manually pumped faucet. Next to the sink is a small but usable formica countertop with a trash can hidden under a removable panel. Across the aisle is a two-burner alcohol stove. And there is a sit-down dinette table that can convert into a bed (for those shorter than 5 feet). The "step" to enter and exit the cabin is a large Coleman cooler for food storage. Everything is laid out in a usable way, and an overnight for two adults is perfectly do-able. The closer you get to the end of the season, the lower the prices will get (although they'r pretty darned low already). Hold out for one that isn't a fix-up project.
Check out the pictures of the new design interior at this link:
http://catalina.sailboatowners.com/index.php?option=com_adsmanager&Itemid=254&page=showad&adid=13915
This boat is for sale right here in the forum classifieds. It also shows a snap-on wrap around fabric enclosure for the pop-top.
Oh, by the way... if you have a big honkin' tow vehicle, or plan to keep it in the water, the Catalina 25 is a no apologies overnighter for two! I've included a picture of a well-matched Cat 25 tow vehicle for reference: