Well considering you attempted this 4 hours before the deadline I'd say you gave it your best shot. Particles are nice, I had a friend who also tried this "close but not too close" idea before as well so I'm always a big fan of that...
But I think a certain comment summarized the problem quite eloquently: "I seem to do better when I don't do anything". The initial configuration, no matter how artistic, leads to this awkward situation where if you stay in the center you'll be able to survive for a very long time.
Nice idea, but please give yourself more time to work next time. Cheers!