your project looks awsome! 
but, lets get to the point, your guns, the guns look awsome and for the sake of weight I would choose a bullpup design (magazine thingy is behind the grip, makes it more compact) so you might want to take inspiration from the Famas a french made bullpup rifle. so it isn't that bulky, good for CQC well, decent a smg or shotgun would shine there. but you also get a good amount of accuracy and range. very important, a variable scope that is linked to your visor is handy for zooming in and more accurate shots. a electromagnatic rife or guas rifle (think railgun) might be more sci fi though, it doesn't use any chemical reactions to ''fire'' the gun, so no smoke trails for tracking you in the distance, no bullet casings to use as clues/breadcrumps. you get it probally. a energy weapon that shoots plasma might be a bit too power consuming ,since it uses a electromagnetic field to keep it enclosed, which needs to be supplied with (1)power at a (2)distance while (3)traveling, and removing it just before impact. its strong but probally still only on a big space ship.
as for the suit(s) I would go with a fully closed off design, you do not want those crazy fantasy bugs exposing your brains to weird toxins do you 
and you can use the helmet to lift the limits humans have on their view width. you can create cameras around the helmet so she can see a 360 degrees around her at all times. so no rogue will think of sneaking up on her back! 
maybe add some kind of external skeleton on the suit (exoskeleton intergrated into the suit) for maximum awsomeness and ofcourse being able to use those big ass sci fi melee weapons is also a plus , a small hip pocket with a tactical knife is handy which might be able to double as a plasma cutter. , a slot for a oxygen tank on the back or neck for underwater combat with those fantasy fish races. or do the classic ''dynamite into a pond'' trick. you need a communication device, so maybe a little antena on the helmet ? a couple of high explosive to breach a castle wall? or a laser designator to indicate the area a space ship needs to bombard from orbit? ( if not energy weapon google kinetic bombardment satalites). thats some next level micheal bay. I could go on and on as you can see. but I will leave you with this first.
Good luck
) it kinda just came out like that. 
Field of vision is definitely important. I will have an drawing of an exoskeleton. I was thinking of her having some kind of nanits that can become anything. Think Bayonetta with her hair being her clothes but nanits instead. A knife on the hip? Got it. 
Ok so my brain is working and its telling me that she can be some sort of android made from nanits or an alien with nanit nanotech stuff. I know what you mean with going on and on about this stuff. 
I believe the reason I have a lot of Marc influence is because seeing his art and watching his videos is why I started doing art again. Honestly didn't know who Moebius was so I quickly looked it up. Interesting stuff there.
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