"When you say symmetrical spread, do you mean having the particles fire out at evenly spaced angles from each other?"
I guess you could phrase it that way, yeah. It bugged me that the particles would have random spacing instead of it being uniform, it wouldn't be a problem if the particles were generated at run-time and thus different every time, but since it's being saved to a spritesheet and looped (e.g. a missile explosion) the gaps become very visible.