I thought they were quite predictable targets:
The Mother Figure
His best friend
His(apparently) most valued colleague...
ALSO;  the 3 people who knew most about the cases/Moriarty.

The three people selected represented:
Home life: Mrs Hudson
Personal life : John
Professional life: Lestrade, because without Lestrade's approval, Sherlock would meet dead ends trying to solve cases at times.

Attack someone on those 3 fronts & they know you mean business. Why not Molly? She would be considered by Moriarty to be an 'underling' to Sherlock in professional life.

There was a clue to each of these being selected. The IOU only appeared in 3 places:
On the apple, in his home : John
On the wall looking directly toward 221B : Mrs Hudson
On the building windows opposite the police station : Lestrade.

As for Sherlock's plans after his suicide seeing as he had no knowledge of Moriarty's suicide; that's an easy one. Think back to the canon.
Sherlock intended on taking Moriarty over with him. Both 'bodies' rushed away & Sherlock would have open slather on interrogating Moriarty all the while both of them presumed dead. Moriarty's network would not have been looking for him to save or protect him.

Things didn't go that way, hence he had to think fast on his feet & as he needed a witness to verify that it WAS him that died, he had to make John his eye witness, as much as he knew how it would affect John.

kazza,

Undoubtedly you are correct about Sherlock's plan to take Moriarty with him. I should have realized, based on the canon, that this would be Sherlock's plan. It really is the only satisfactory explanation other than acknowledging a plot hole (which I'm sure none of us would ever even suggest...).

One question, though. In the canon, Holmes doesn't plan to survive the falls, and pretty much is thinking on his feet as events unfold. Here, Sherlock does plan ahead, and expects to survive. If your theory is correct, you must assume that Sherlock planned on jumping before he knew about the assasins. Why? He could much less dramatically (oh, is that reason?) whisk Moriarty away for interrogation. Neither plan involves Moriarty's henchmen knowing what happened to him (unless Sherlock assumes they watch M's every move, in which case they certainly will be looking for M now, as they know he went to the roof and didn't come down).

I'm not as convinced about the 3 peoople chosen by M and Sherlock. Your explanation will work, but I think others would as well. Just leaves a bad taste in my mouth (but, I won't go so far as to blame the writers--if it's a stretch, I suppose they've earned one or two of those).

One more thought:  has anyone suggested that maybe the gunmen we see are actually hired by Sherlock (or Mycroft), and not Moriarty? I mean, Moriarty wouldn't actually have to have gunmen in place--just telling Sherlock that would be sufficient to get him to jump, wouldn't it? Perhaps the gunman on John was there to protect Sherlock if something went wrong on the roof. How could Moriarty have planned to have his gunman set up (tripod and all) in a precise spot to have a good shot at John, since M didn't know where John would be? And the same goes for Mrs. H. We assume the guy with the gun is M's man; maybe he is there to protect Mrs. H, since Sherlock & John can't do so. I don't know; just seems that maybe we're seeing what the director's want us to see...

hypergreenfrog wrote:

the only reason why I personally would have expected the writers to maybe make Molly a target as well is because - as a non-canon character - she is ultimately dispensible. Everybody knows that the snipers won't kill John Watson, but we no nothing about Molly's fate or future.Therefore the writers could have added another twist to Reichenbach, or to the first episode of Series 3, by having Molly killed by Moriarty's men. Luckily for her, they didn't 

We actually have no idea how many snipers Moriarty actually had in place. We know of the three, which happened to be the same ones Sherlock guessed, but there could have been others. I wouldn't be happy if when S3 begins we find Molly to have fallen victim to Moriarty's crew, not after what she did for Sherlock right before the fall. I LIKE Molly.... I hope they keep her around.

ancientsgate wrote:

We actually have no idea how many snipers Moriarty actually had in place. We know of the three, which happened to be the same ones Sherlock guessed, but there could have been others. I wouldn't be happy if when S3 begins we find Molly to have fallen victim to Moriarty's crew, not after what she did for Sherlock right before the fall. I LIKE Molly.... I hope they keep her around.

Neither would I! I like Molly too, and hope they keep her as a character. I just wanted to point out that "threats" such as the three snipers only work well in stories with an unknown outcome. Killing off John Watson would not be feasible to most fans, even if they haven't read the canon. Therefore the sniper sent to kill him does not actually pose a real threat. The other two targets are also taken directly from the original ACD stories, if less well known. Therefore, Molly would be the only person who "could" be killed off without moving too far from the canon. It's just a thought, not saying it's what I would like to see.

I don't know if we had this already. Found it just now.

To me this looks as if he'd slide over the edge?

He's on a wire, tho.

Fine, but what do they need the wrong placed cushion for, then? 

But it isn't red. Does a green one work as well?