The only way to improve game balance , interaction and tactical focus in
40k, is to write rules for
40k, NOT
WHFB then add in loads of exceptions omissions and additions to arrive at a sort of rule set that sort of works.
40k NEEDS a complete re write from the ground up to get any level of improvement with out adding even more complication..
There have been loads of great game mechanics and resolution methods developed since
WHFB rules were written .
GW 40k rules use NONE of them!
Basic Idea for
40k home brew rules.
Start with Epic rules(Net Epic/Epic E.A.) , ADD detail , (to scale the game play up,) Job done.
Basing game development on MODERN battle games , would allow far more game play with far fewer pages of rules .