Minor Wording Issue
I think the wording of the proposed 2.4.2 is less than ideal. "2.4.2 Meeting format, classes run, track specification, Prizes and scheduling are at the host club discretion."
I do not think you really mean that track specification should be at the Host Club's discretion. I think you mean that the host club has the freedom to arrange the circuit as they wish within the constraints of Section 3 (notwithstanding 2.3.3). This may seem obvious, but I promise you someone will wilfully misinterpret it and no one will be able to stop them when the time comes.
Most Proposed Changes Look Pretty Reasonable
Otherwise most of this looks good, worthy of consideration anyway. I haven't gone through things with a find tooth comb, but on first glance I like the increased flexibility of Section 2. The proposed 3.14.5 is sensible and has been a matter of controversy for a while, so this should clear that up.
I like 6.5.2.1 Limiting people to two spec motors will go a long way to stopping wallet racers bolting in a new motor any time its necessary and overgearing it for one super run.
Changes to Qualifying and Final Formats are Poor
There is only one area where you are definitely going backwards.
The changes proposed to the provisional qualifying order and the finals are going to recreate most of the problems that were fixed in the last proposal voted in ~3 years ago.
Take the first part: "6.9.12 The format for counted rounds to determine a driver’s provisional qualifying position will be based on dropping their worst two (2) scores out of the qualifying rounds."
The provisional qualifying order concept was introduced to create consistency between what happens normally, how regrades take place, and how qualifying positions are determined in the event of wet weather or cancelled rounds. The goal was to eradicate any confusion for drivers and officials, because the same system would apply no matter what.
Under the current system a driver can go and look at the board, see where they are qualifying, and know that if it pours down with rain at that instant that is where they will qualify, or if a regrade takes place then, then their current position as displayed on the board is the one they are regraded into.
You've now half changed this so that wet weather is dealt with differently, and changed the formula for the provisional qualifying order. The computer system will now have to be changed if it rains, and drivers will find themselves in a different position to where they thought they were. Guaranteed this will lead to someone not applying the correct formula and someone missing out on their rightful final spot, because that type of thing has happened before.
What's possibly worse though is that nobody seems to have noticed that the provisional qualifying order would still apply to regrades – with the changed formula! So, what now happens at the regrade after round 2 when the formula says you have to drop the drivers' worst two results? Prior to the latest change, how the first regrade was supposed to be applied used to be a source of confusion with different people doing it different ways. The last few meets I went to under the old system there were always arguments.
The changes to how the result of the finals is calculated produces exactly the same result in 1 or 3 leg finals. In 2 leg finals, which you might have for a B final say, you're now counting both legs. Was that the intention?
Previously the rules were written in such a way as to allow the rule set to be used at events with more than 3 finals. AARCMCC events are 3 finals and there was/is a rule that specified that, but part of the prior change was aimed at producing greater utility with the rule set, and making it easy in future should AARCMCC clubs vote to go to more than 3 finals. The proposed rule change does away with this without any significant advantage.
The change to what to do for finals in the event of wet weather, I have to say I'm not a fan of. Why should the pole sitter get an automatic win for the 3rd leg if it rains? There's too much emphasis on qualifying as it is.
Imagine this. The 3rd and 4th qualified drivers have a win and a third after two legs. The pole sitter has a 2nd place and a 7th or something. It rains, the pole sitter automatically wins the 3rd final, and therefore the event. Doesn't seem fair.