That makes sense. The faster the ship would go, the more 'kick' the particles would get more dense and more kick. I suppose you could do that if you could mount particle generators on ships or subsystems and change the values via scripting depending on the speed of the ship. That's kind of a long ways off right now, though, unless somebody else wants to try to code that in. I'm not sure if it'd involve updates to the particle code, but it'd certainly need more complete support in scripting (a particle generator class, etc.) and I don't have the time to do all that right now.