Just before I begin, I've had a thoroughly enjoyable time reading this topic (only managed to read from page 12 to this present one though - all your posts and theories are very interesting!). I might hang around here more often now, as this place is surprisingly nicer than the Music forums...
Anyway, I've not got a theory as such (though I do corroborate others', even the smaller things like the significance of the tea service), but one thing I have a major irk with is some of the theories that suggest that Sherlock planned to land in a positioned rubbish truck or that Mollie accompanied Sherlock to the roof to fake his death because, fundamentally, Sherlock wouldn't have been able to plan those theories.
Until about five minutes before his jump, Sherlock knew he had no other option but to jump to save Watson, Lestrade, and Mrs. Hudson, and I genuinely believe Sherlock was surprised when Moriarty killed himself; he didn't expect it at all. To me, the conversation before Moriarty's suicide recalled the scene from 'A Study In Pink' where Sherlock is talking to the cab-driver in the school; ever-so-slightly peeling away his stone cold façade to reveal a very insecure man (the best part being that Sherlock thrives off the moment when his opponents' pupil's dilate and their pallors fade as he unlocks their plans). And this means that any plan Sherlock had before stepping onto the roof would have quite literally gone out the window. Tossing a corpse/Moriarty's corpse onto the pavement/squeezing some blood over it/him/jumping in a rubbish truck are all impossible theories because Sherlock never planned for Moriarty to kill himself, so why would any plan he had thought as he stepped onto the rooftop involve the corpse of Moriarty instead of a living, breathing and wonderfully psychotic Moriarty ready to kill Sherlock's three closest friends in a heartbeat unless he saw Sherlock impaled on the pavement? Sherlock could not have prepared such a plan to escape as the theories above because, until Moriarty killed himself, any plan Sherlock did have would've been to evade Moriarty as someone who was very much living. But then again, this plan would've been foiled almost immediately because Moriarty had John, Lestrade and Mrs. Hudson at gunpoint.
So just ponderings really. I'm very interested in hearing more of all your brilliant theories and ideas and hope you all withstood my post, even if i rambled a bit/was possibly unclear.