Im not exactly sure increasing drag or something similar to it of the front is the way to combat the high pack speed, since several other factors play a large role in keeping the speed high. Without loss of speed in cornering or the ability of other riders to slow you down outside of sticky draft, ie its pretty easy to move around in the peleton, the natural speed will be a lot higher than normal. Setting up some sort of penalty to offset these could lead to it being even harder to actually attack and stay clear since whatever penalty applied for moving past the front of the peleton also applies for attackers be it solo or smaller groups.
There definitely is a problem with the churning of riders in the front, but without actually having solid riders and steering required to move around the peleton, the options are pretty limited. Changing it could very likely make it worse or have consequenses that just moves the problem instead of fixing it