If you have time I have one more idea, flare powder. Burns very hot. I don't really care about color, but i think it should be red or green. It also should have a small flame that doesn't fly around. If you ever saw one in real life it has kind of a spark looking flame. I think it would be pretty cool. And it should burn slow.
It's TPT its "not real life" as you always say. EDIT: http://www.youtube.com/watch?v=RsbqHcVe4BE I know its not all green but still some is. Either way i agree it should be red But green wouldn't be bad.