Edit: Whelp, First double post on forums. I'll go to find a nice corner where I can feel bad about it. atleast it was about something that just might warrant a new post anyway (excuses) 

Well, while I was procrastinating (It's weekend though...) I actually thought of 2 thing.
One is Shields in general. would they work? Would it add to or detract from the experience? I can't say for sure but that's just one thing that came to mind.

The other is of course: the "175 Recoilless Rifle, Magella Top Cannon" from Gundam.
To make it roughly approriate for our scale it would be [url=https://en.wikipedia.org/wiki/Cannone_da_47/32_M35]44mm (anti-tank[/artillery]) cannon[/url]
[img]http://vignette4.wikia.nocookie.net/gundam/images/c/c1/Magella_Top_Cannon.png/revision/latest?cb=20130820130245[/img]
[hider=Held]
[img]http://www.geocities.ws/gundam_uc_0079/images/MS-06_MTC.gif[/img]
[/hider] That's just my 2 cents. It'd be hand carried in 2 arms though.