First, I need to define a counter. This is a pokemon that you switch in which creates a situation in which the foe would be better off switching out. Weavile is a good Salamence counter, as an Ice Shard is enough to bring it down, so the opponent should switch out or lose Salamence. However, a counter need not be a sweeper. Skarmory can switch in and counter Haxorus. Even though Skarmory won't KO, it will still be able to plant layers of Spikes, and Whirlwind away Haxorus if it tries to set up. Thus, it is advantageous for Haxorus to switch.

I listed every usable set (thanks, Smogon) of every pokemon with a usage of 0.5% or higher (thanks again, Smogon). This is about 500 sets, from Dragonite down to Yanmega. I put all of these onto a spreadsheet twice, once for the X-axis, and once for the Y-axis.

Here is my plan. I'll fill in each cell in the table this forms with a number. If a pokemon in the Y-axis counters one in the X-axis, I will fill in the cell of their intersection with the product of their usage percentages. If that pokemon does not counter, the space is left blank.

At the right edge of the spreadsheet, I put a cell per row that contains the sum of the numbers in that row, divided by the percent usage of that row's pokemon (the one on the Y-axis). This gives me the sum of the percentages of the pokemon that this pokemon counters. I think this is a sensible way to create a value for the pokemon's ability to counter foes, since this is relative to the odds of a certain foe appearing. For instance, Heatran counters both Ferrothorn and Bisharp, but countering Ferrothorn is worth more to its score, because Ferrothorn comes up as a foe more often.

At the bottom of the spreadsheet, I put a cell per column that contains the sum of the numbers in that column, divided by the percent usage of that column's pokemon (on the X-axis). This result is the sum of the percentages of the pokemon that counter this pokemon. While the number to the right reflects competitive strength, the number at the bottom represents weakness.

To provide a total value for a pokemon, I simply divide the % sum that it counters by the % sum that counters it. The values that form are, literally, the ratio of a pokemon's ability to counter to its capacity to be countered.

The impact of these numbers, once generated, would be astronomical. We would know, numerically, which pokemon is the best at sweeping, at stalling, and at setting up a variety of effects including Wish, hazards, and screens.