Possibly just a toy, but I suspect it's in the movie... Cant' tell if I like the Extra Reloads on the chest or not...

Cool!

I've always liked the Aliens heavy weapon mount concept... (although it's very impractical in real life)

It looks like modern military changes from 70's to 2010's is affecting design. You have several magazines high up on the chest and a sling that looks more complex then just the shoulder sling we've seen in the OT. I don't think I have a problem with it. I did love the WW1 and WW2 look in the OT weapons, but I figure the artists are trying to convey the 30 year gap.

For game purposes, the multi-magazine hardmount looks like an armor attachment to me. Perhaps it allows use of Extra Reloads with an Incidental instead of a Maneuver? The holster for the blaster pistol also seems like an attachment for the armor?

Those "reloads" could also just be thought of in a game as a modular portable power pack supply. Several power packs to supply the weapon. Normally used as just one system, but also modular so that any individual unit can be changed out as needed. Militaries love modular parts. Easier to maintain systems; faster to fix and refit; and cheaper to buy.