Second one is a massive improvement. I agree about face/head protection (pony tail w/ goggles would be fine, but so would a sufficiently purty helmet) but as is is fine as well. The Rule of Cool is paramount here IMO-- just being an all-girl power armor army you've committed to RoC-compliance.
If I could make a suggestion... the pose on the bike is very important IMO. Leaning back implies cruising, like on a harley, as well as brute muscle power. As your pose leans further and further forward, you imply more sprinting and aggressiveness. Most of GW's bikes have their riders leaning way back, like they're going "putt-putt-putt" on a massive chopper. An artifact of heavy metal and 80's biker culture, maybe? The newest Dark Eldar jetbikes lean their riders far forward, more reminiscent of Akira and the anime/martial arts movie aesthetic.
For a female army, I think leaning far forward is much better from a Rule of Cool standpoint. Start with the girl and the pose, then mold the bike around it. Happily, this also means less dead space between her and the bike, which solves one of the problems you identified. I tried googling for a pic that illustrates what I mean but all I got were pinups. So I looked for GUYS racing motorcycles and found this:
http://fastbikes123.blogspot.com/2011/0 ... sults.htmlNotice the poses they're using? For this model, I'd arch her back a little more, rather than hunched over like in the pics, so her butt is up a little higher. Keep her hugged tight against the bike (looks good and eliminates dead space). On a bike with a helmet, you lose the two most obvious visual cues of her gender, so showing her figure is important.
BTW, the tail pipes are fine by me. The thing is, Deacon's models so far aren't exactly steampunk, and they aren't exactly high-tech. But they have a very strong visual identity of their own, and that's consistent across the models we've seen so far. If you're committed to fusion power, then just say these are rocket-assists for bursts of speed and clearing obstacles.
