Personally, I would like to see something like an experimental plasma rifle/LMG. We know there aren't any fast-firing plasma weapons, so why not have one? We've got tons of other ones, so I think that one plasma one wouldn't hurt. It would weigh a lot and eat up Microfusion cells like...something hungry, or any other forms of balancing. It would have like, 10 shots per MF cell. I was thinking it would look like this:
http://i1223.photobucket.com/albums/dd507/Chris_The_Mushroom/myweapon-5.jpg
Now, post your ideas?