Is there (or will there) be a unit modding guide (akin to kekvit's new unit guide) available yet?

To be honest, I got to grips with the files in the MTW folders pretty well but the little chat I have seen about RTW seems very confusing so far.

LIke MTW I want to do a few simple things.
1) add/tweak units
2) add/tweak buildings
3) add/tweak starting positions/province owners etc

Could someone point me at the right files? (is it as simple as MTW?)

I also thought if there is someone out there who has good historic knowledge we could get a list of all the units/buildings etc that wernt in the game but should have been together.

Any thoughts?