There are players throwing 150 discs already, that achieve over 400' already with current technology discs. And in some very low turn discs there is almost no other adjustment to make other than distance control. I was told that R-Pro Bosses are made with a different mold than Stars. I can control 160 R-Pro Bosses and the need for adjustment to a different mold Star Boss is large. If a durable 160 Blizzard Boss of the Star Boss flight behavior and no need to adjust was doable i'm sure i could control a 150 at least as much as a 160 R-Pro Boss. And i would try a 140 for hot rod duties, because it is good to have tail wind and uphill or over the trees options for long ranges or hyzered/anhyzered shots. Not to mention ultimate distance :-)
But there is always the chance of an errant shot or wind gust making life more difficult. That is why i'm not sure if it is a good idea for the safety and good of the sport to go too low in weights. There will always be someone trying to get an advantage throwing dangerous shots. So if a weapon is put in their hand and it gets away from them it won't be good for anyone. That is why i would like to see a manufacturer self imposed lower weight limit to not only lessen the chances of litigation and damages, but for the overall benefit to everyone, who plays.
I won't dictate any weight numbers, but am inclined to think that even a 140 disc will be dangerous in the hand of 400'+ throwers, who by now are getting more numerous. Give such a disc to a 370' crowd and a lot of people are throwing 400' and the 400' and over people are getting crazy distances at less control. So it is up to you to decide how much change is good for the sport and at which weight for given turn and wind handling for which throwing distance control over the flight is not reduced to dangerous levels.
With that said 159 Vulcan is already dangerous to 400'+ throwers as it is. It is fast and holds the turn forever, glides well and fades so late and little, that it goes a mile maximizing the glide staying close to flat longer than just about anything. No tolerance for error at all and very little gust handling or headwind toleration for 400' throwers.