I'm just about finished restoring my 71 Venture 224. Someone asked me how many people can I take? I've discovered that boats manufactured after 72 have a max capacity plate. I found a Coast Guard formula # people = length in feet x width in feet / 15.
On my Venture that would be 12 or 1500 lbs. Sound right? And of course that 1500 lbs includes gear and the motor so I'm thinking 6 or 7 people as thats really all the space there is.
So am I close?
I think the capacity plate only applies to power boats, or dinghy-like craft. Even if it applies to the sail boat, the safe number will be less because of cockpit size and the need to be able to operate the boat, lines and sheets, in a crowded cockpit. Even if just motoring, the cockpit seating is likely to be a limiting factor, can you imagine a bunch of folks on deck who all went to one side at once?

Generally, I doubt that the CG numbers apply to people standing in a small boat, which they might do out of the cockpit. Also, 'gunwale' riding is not generally legal on a power boat, which a sail boat is if the motor is running. The only 'out of cockpit' permission that I know of under power is for crew operating the boat, such as raising or lowering sail. 'Gunwale Riding' is only OK for rail meat under sail as far as I can tell.
For example, I think that I would limit my Catalina 22, similar in size to your boat, to 5 or so for sailing, and 6-7 if only motoring. Others may have a different 'number', but that is all that I would feel comfortable with. Under sail, remember that the crew becomes a larger proportion of the ballast as the weight of the crew goes up. I know of a local sailing instructor who once sank a J22 when two heavy students refused to move in a tack...
OC