The problem/question is this:
Will more collector Army Builders buy more Troopers...
OR...
Will more general people buy Vaders/Lukes/Bobas/etc.?
I'm not saying I know-- or any of us do, really-- because we're never going to buy those goofy Saga Legends Vaders that Hasbro keeps making and selling by the bushel. Exclusives are not sold exclusively to collectors, and it seems that their goal with 2-packs is to put one "general fan figure" in there so someone buying for a kid or a gift or whatever will go "I don't know what this guy is, but I want to spend $10/$15/$20 and this has a Darth Vader in it so at least I know they'll like that. I am a wonderful aunt/uncle/creepy dude on the subway." (Examples: Vader/Palpatine in the Squall sets, the Order 66 packs, most comic packs.)
And the days of the $10 2-pack are *over*. The $13 one is probably limited. I'm sure they'd be a huge hit if sold at cost or a loss, but unfortunately those kinds of loss-leaders are uncommon. Until Christmas rolls around, anyway, things go crazy in Nov-Dec.
Troop collectors do eat up a lot of figures, sure, but the appeal of generic figures is pretty much exclusively focused on that audience, whereas a someone with an actual specific name tends to have appeal to a more general audience. I'd personally prefer to get something new OR troopers over Vader #57, but that's me. That, and you never know how "full" a trooper collector may be. I've got PLENTY of Death Star Troopers to the tune of my not wanting any more, ditto Rebel Pilots due to the various specific ones being made over the past 12 months-- but again, that's me. (How many did we since 1/1/08? Like 15-20?)
You generally want a figure in each set to appeal to a group outside the likes of us, and while I personally would love to have a couple of those, DS Trooper and Yavin Honor Guard? Really? Wow, I dunno but that sounds like retail poison to me.
On the other hand, hopefully Hasbro is listening and says "Hey, you know what'd be awesome? Clean shaven Legacy Hoth Rebel vs. Snowtrooper."