a few specific "how to mod x" questions

1. I want rank bonuses for spear units back in. Can this be done, and if so, how?

2. I want to disassociate family fertility from empire size. Is there any way to have my family tree expand "naturally" with no attention paid to the number of cities I have? If so, how?

3.a. I'm okay with cav speed, but I feel infantry sprint speed is much too high. I am aware that individual unit class speeds can only be changed by modding the animations (as speed mods based on terrain affect all units equally).

3.b. Also, Hastati are listed as Light Infantry, though I assume Velites are too. Velites should of course be faster than Hastati, and Hastati faster than Principes and Triarii I guess. Is there a way to do this?

4. I'm still deciding whether I like the kill speed. If/when I want to change it, how do I do so?

5.a. I have the impression that the range advantage missile units get from height has been nerfed in RTW from MTW. How can I increase the range bonus archers get from being higher than their target?

5.b. I have also noticed that missile units will often shoot with a relatively flat trajectory when shooting downhill. Before 2.1 this was disasterous for any friendly troops between your archers and their target. How can I force more arch into the trajectory without changing the range?