My wife and I took a week long trip to Catalina Island a month ago in our 1974 Catalina 22, and everything went great. We even went to Cat Harbor on the backside of the island which was awesome. With the swing keel, we could anchor for free in the shallow mudflats inside the moorings. We were the smallest boat back there by far.
Just make sure everything on your boat (keel, rigging, hatches, etc.) is in solid condition, and that you have the ability to reef/reduce sail area when it gets really windy and you'll be fine. Also, bring a lot of fuel for your outboard in case there's zero wind and you end up motoring the whole way!
If you're not going in the summer, you need to have a plan for dealing with the possibility of Santa Ana winds. This book has great advice:
The Cruising Guide to Central and Southern California: Golden Gate to Ensenada, Mexico, Including the Offshore Islands by Brian M. Fagan
Also, you have to cross one of the busiest shipping lanes in the world, and the C22 is a pretty small and slow boat. Make sure you have a radar reflector, flares, VHF, horn, etc. and watch very carefully for big ships.
I tow my Catalina 22 with a 1987 Volvo station wagon where I've upgraded the suspension, brakes, and cooling system to easily handle the extra weight.
The biggest downside is that my wife and I are really tall- and everything in the C22 is sized for shorter people. I think if you're over 5'10" or so, a C25 is a much more comfortable choice unless you like bumping your head on bolts, and sitting/sleeping with your head on your shoulder.