I'm surprised you think the worst is the MA1 division. I would think that those are the better players and would be more aware of their distances and when it is safe to throw. I would have expected the 'backup' issue to be the lower AMs (MA3, etc) who sometimes think they throw farther than they really do - or who had that one awesome long shot and think they will do it again - and wait forever.
One thing I wish disc golf would 'copy' from ball golf is "ready golf"....ball golf used to be "better score tees first"...but they changed to "ready golf" and it speeds up play. Disc golf could learn from that. I throw a fairway driver 250 feet forehand (backhand it may be going anywhere - even backwards), so if my card is on a 500 foot hole, why waste time sitting there when the group in front of us is 300+ feet away from us? Maybe others on my card can make that distance, but I can't, so playing ready golf would let me go and by the time I'm done throwing the group in front should be out of the range of the rest of the card. That speeds up play. Admittedly, in disc golf it's not that big of an improvement since our distances are shorter, it may rarely happen.
((In the league I play in we will tell 'shorter throwers' to go throw first if it will speed up the pace of play....if my card is sitting waiting for the group in front to move out of range, I will ask if I can throw as the group is usually out of my range...I normally get the okay as my group knows my ability (or lack of it).))