I have never hired more than one. I usually try to find a buddy or a neighbor first. If it's late, I go to MP. I ignore everyone flooding or begging, doing stupid little "I need to feed my kids", etc..and hire the ones that are politely standing there.
I have 5 kids. If someone is bickering, I'd leave and come back. Or, ask the developers to put in a ceiling fan and give us duct tape. We can it there and watch them bicker as they spin around.
I always harvest in a line of, 7 across and 5 down. That way, I keep one space if they hire more than one to harvest and plow. It amazes me how many are vultures, however. They don't respect that and are clicking their mouse all over the place, trying to grab what is there. Um, it's a game for fun! Geesh. I will then ignore the vultures so I never hire them on my farm.
I have tranquil farms of beach communities and campground. They better behave!!! lol