The B-Wing is gonna take up a lot of space in a pack due to its shape. Not a lot bigger than the Y-Wing, but awkward, and I can imagine it being somewhat more fragile because of the thinness of ship.

Prathin said:

I bet if you made it face outward like the TIEs, and put it's long axis at an angle, it will fit well enough in blisters. As far as thinness, I don't expect it will be much thinner than a TIE Fighter's wing pylon.

As for thinness. I have actually been surprised at how durable my ships have been. I haven't had anything break or really even bend. The Cannons on the X-wing and the Wings of the TIE's are both pretty thin.

My core set X-wing has the starboard laser cannons pointing in opposite directions (one port, one starboard) and the lower starboard thruster is turned medially. Overall, it's a pretty mangled looking X-wing so I can't say that thinness isn't an issue for these miniatures. Mind you, I'm talking about the state the ships come out of the box.

(My Y-wing's thrusters are not parallel either, but that's not a thinness issue.)

It's probably completely too late, but I have read of a 2-man version of the B-wing. I first found it in "The Star Wars Rules Companion" which is a 1989 RPG rules supplement. But when I just now went looking for more references I discovered it is also here.

http://starwars.wikia.com/wiki/B-wing/E_starfighter

I just hope that FFG had the foresight to add a pilot card with a co-pilot option.
That would make for some interesting combinations.