I have long wished for all of organized football from HS up to develop a consensus rulebook. It could be written in such a way to have variables to keep the integrity of the rules for each, but we should be able to reach one standard field with the same hash marks and same goalposts for example. I would think agreement could be reached on whether one foot or two feet inbounds for a completion. I would also think penalty enforcement could be standardized. Where there were fundamental differences they wanted to maintain, the the rule could have H C P alternate rulings, i.e. H and C could have play ends when ruled down regardless of contact, but P could maintain the ball carrier could get back up in absence of downing contact. Need to maintain different pass interference rules same deal. Any number of variables could be reduced. I would call it the KISS football rulebook It should be limited to everything and only on the filed of play and each level could maintain their own organizational book for off field issues that are unique like squad size, recruiting/draft, post season structure, pregame administration, uniforms etc. Overtime could be a real interesting discussion. I don't know if there are any on field issues that could not be resolved with this format though. I would imagine a lot of things could be cleaned up as each levels play book has evolved over the years.
Besides not being as confusing for players as they progress through the ranks, and fans trying to watch 3 different rules every weekend, it SHOULD really improve the quality and consistency of officiating. Not a bad goal. I cannot imagine how tough it is to make the move from college to pro rulebook as an official. Years of instinctual reactions have to be tough to overcome. Might explain some of those late flags we always see. Many issues could be resolved with a similarly structured book of rulings on the rules or each level maintain it's own to speed up the process rather than have to go back to a conference table to alter the universal rulebook itself. For example how much contact is allowed down field. It can still be defined as illegal, and the penalties for illegal contact can be defined, but the interpretation of the one rule could be different by level. Still end up with one rulebook for the rule and the penalty statement.