I actually like not being able to control the Miis' every whim and movement. I feel like it adds a level of drama and surprise to the game. I do wish, though, that we could have just slight influence over some of their decisions. Like instead of asking what we think of a certain Mii, they'd ask which Mii out of three or four would be best for them to date.
Actually, one of my Miis was interested in two people and she asked me who she should ask out. That only happened to me once, but two Miis sounds more reasonable than three or four honestly.