About the Succubus, I think what the designers intended was that the creature dominated due to the intrinsic effect is meant to be controlled by the DM. I'd argue that a summoned creature is only under player control if the player issues a command that round, and if the player does not issue a command, the summoned creature is no longer controlled by the player. Thus, the DM takes over and declares what it does based on the intrinsic description, which includes then dictating what the resulting dominated creature does on its turn.
I admit it might be a little weird, since the DM is dominating an NPC with another NPC, but that's not only more fair, but also adds a lot more potential danger to the summon. I'd imagine a summoned Succubus would take the first chance it could to dominate the summoner, thus making the summoner unable to give more commands (until the succubus misses). I don't know about anyone else, but that drawback is fairly balanced with being able to dominate at-will at level 9.