Why would we want to do this? Well we've seen cases in the past where one or more cars in the same class and race are substantially slower than the rest, so that they become moving obstacles for everyone else. This is really unfair to both the slow cars and the rest. In order to avoid this, we can consider introducing a "percentage" rule similar to F1.
I've been playing around with various percentage numbers and have come up with the following chart showing how this will affect qualifiers using first a 115% then a 120% factor:

Let's hear your thoughts on whether or not this is something to consider and which of the two samples is better. Of course we can also do it with other percentages and compare the results.