Where are you located? Are there active cat/F16 racing fleets near you? If there's a fleet/club not to far, you might want to show up, talk to some of the racers, see what they've got, see what you like.

It's hard to find a 'one size fits all' racing boat, the racing boats are designed to go fast, at a certain all up weight. I'm not saying you can't load up an F16 with 4 people, but two of them had better be little kids. Then there's the dagger board issue, ie. if you're going 'cruising' you don't want to be having to worry about hitting bottom, with your 'racing boards' ($400 each to replace).

I found an old Prindle Escape for $500, wich is what I use for 'play time' with the kids, the dogs, who ever wants a ride, etc. but the Blade is just for racing.