For me personally...
I think it is a matter of personal taste. Personally, I like hunting with one dog and one other person. However, this is largly because of the type of habitat I hunt. The cover just isn't big enough to warrent two dogs and there really aren't that many birds to go around. I'm selfish, I want him on as many birds as possible. Now if I hunted out West more (and I wish I did), I can see where I would be more open to larger parties and more dogs.
For me there's just something more intimate about hunting with my best friend and one other person. That way my dog can really get some work in.
For what you're describing, a short 2-4 hour hunt on a preserve, 3 dogs and three guys sounds a little crowded to me. I have hunted a preserve with one dog and three guys. I had the guys stay together as the dog worked. That way we minimized any wild flushes. I then rotated the guys on points. Everyone seemed to enjoy it. Maybe you could do that and rotate dogs. Hunt each of them for an hour or so? Either way, 3 dogs in 3 hours just isn't a lot of time. Then again, if you're working on honoring and backing, this might be an ideal situation.
As to pointer vs flusher... Sounds like you've made up your minds.