Don't leave a voicemail, seriously.

Your last point has actually been a source of a lot of pondering on my part. For me, the big hitch to creating the meta text of the film is trying to figure out who each of the dream characters is to Dom. I'm pretty much now of the opinion that Mal and the kids are completely symbolic and never existed in the real world. Mal is something his subconscious knows he has to put behind him/get over and the kids are his reward for doing so/something he aspires to but can't achieve with Mal lingering around.

Who the other characters are is more difficult. I think Ariadne might be himself--him talking to himself and ultimately solving his problem. The other characters I'm more unsure about. Maybe Arthur actually is his partner, what that means I'm unsure. But he does trust him implicitly and believes that he can do the impossible (the hallway scene, the whole movie really).