The answer to your first question will depend on what your end goal is. If you want blue birds you need to breed to blue or splash. If you want lavenders you have to breed to lavender. Cleaning up leakage takes generations.F2 breed back to blue? Splash? Or Lavender? To clean up gold or red.
I just brought home a beautiful lavender roo. Planning to get some Ameraucana hens as well. What color hen to continue getting lavender? Will splash always breed blue?
Sorry so many questions!!