Your biggest hurdle with the vacation pay is that it's based off of 40 hours per week. By paying you overtime you're already getting the extra compensation up front. If they paid you on your annual income, obviously that would be more then 40 hours. Whereas road drivers make straight millage pay for the run whether it takes 8 hours or 12. All that being said, maybe a compromise of paying you on an average hourly scale. So your vacation pay would be based on the amount of hours you averaged per week. The elephant in the room here is that all hours for vacation pay would be straight regular pay... no OT. But it would be better then the system you have now.
The Cali situation is going to be fun to watch. So many variables to contend with. I don't believe the give and take of millage is gone, I think it's wearing a different shade of lip stick. When get down to the nitty gritty, It's just an average of what millage would pay, same as they gry now for the most part.