@Kaiousama: Glad to hear the custom parameter is working so well for animation.
Thanks for your suggestions and ideas. Regarding your feature request about different bitrates for different parts of an encode. This is a really useful feature, and I have seen it used with success in AutoRV9. It belongs either in a GUI or Producer, but I don't really know where it fits best in Producer, cmd line or job file, and either does not fit really well. RadicalEd is right about how it fits nicely in a GUI where you can set up encoding sessions.
A parameter to float bits between high and low motion areas would be a suitable codec parameter though. I will add it to the list of improvements to look into.
Regarding edge encoding; RV9 already does it pretty well, does it not, but your suggestion is a sound one. However, smooth gradients also need their fair share of attention