How to create better fireworks

I have created some fireworks in Blender with particles. And they don’t seem real to me. Do you have any tips for making those fireworks better?

I want fireworks to spread more. Or to come only from certain vertices. How can I do that?

Which one do you thing is better, red one or yellow one?

http://www.youtube.com/watch?v=iuP514Bkpu8 If the video isn’t online yet it will be soon.

I have created IMHO better looking fireworks.http://youtube.com/watch?v=JAPsrYrVC1Y what do you think of them?