Yeah I think I had about the best luck you could possibly have as far as getting the weapons I wanted when I wanted, and such :P. Also I did use some spawn killing with the sniper (look in walkthroughs section for the place) which gave some nice easy streaks in between other killing.
Now here is a truly epic pic... My guy somehow glitched through the roof of the ship in such a way that nothing could hit him, so I left him there until the computer characters all killed each other so there was just 1 left with 6 lives :P.
And also by being extremely lucky..... :P. I did spawn kill some too like I said, and if you kill them as they spawn they dont have time to kill each other.