I like the twin vulcan idea. Maybe also a couple of stingers in this sort of arrangement:
Thanks for the Stinger images.
I have the Takom 1/35 Russian CADS-N-1 Kashtan and I was originally thinking of putting it on the G6 but the Kashtan is too big to fit on the G6. The Kashtan has a huge radar, twin rotary cannons with missiles and looks really cool but just couldn't fit it. Here is mine still in progress.
Here is the real Kashtan. As you can see, I still have a long way to go to finishing mine. Takom didn't include the rotary gun barrel faces, they only included the gun barrel covers. If you leave the covers off, the gun barrels are hollow. In Takom's defense though, some Kashtans don't have the gun barrel faces on the end of the barrels as shown in the second photo.
I was also looking at getting the Italeri 1/35 Stinger Hummer but couldn't find one cheap. I only found one available on Ebay for over $51 USD shipped. The Stinger missiles on that kit would work perfectly.
There is also the Italeri 1/35 Anti Aircraft Armament Set which has an assortment of missiles like the Stinger and Starstreak but you only get one of each. I would need to buy 4 sets and that gets really expensive.