I think your suggestions are a bit over-the-top.
I think a repeat of that Scroll of Resurrection deal is on the cards, a free upgrade to MoP and (maybe) a free lvl 85 will be made available. A mount or something to the person that got their friend interested enough to pay for a month, also along the line of the other SoR, one free server transfer I think - was too long ago - I came back for a few days for that Cata release with the two new dungeons with thrall. 4.3 I think. It wasn't enough to hold me, however, but I think it worked for others. I can't remember if I subbed a month. If I decide to level to 90 with this deal, at least it's 15 bucks they'll get that they otherwise wouldn't have.
I have absolutely no idea what Titan will be, but I do know one thing - Blizzard is in a catch-22 - unless they offer some sort of incentive / migration of characters in any mmo that competes in the same space as WoW that they make, they will self-implode. If there is the slightest slow-down of content release, the WoW die-hards will complain that they're being neglected and that the entire dev team is working on the new mmo (even if they're not related)
If Blizz brings out an mmo that caters to the same market as WoW players, it will compete with itself and it's risky as they need to consider how far they can push the graphics engine - too far and old people won't sub/migrate; too little and new people will think it looks too crummy. In all likelihood, many mmo addicts who have been thinking of quitting may possibly just throw in the towel.
In all likelihood, if it happens that Blizzard brings out a WoW Killer, it will possibly fall victim to WoW's own success. I would hate to be Blizzard right now, losing numbers in a (great) aging game and carefully trying to position themselves to attract new players /or old WoW players back to their new mmo.