Okay Tango so I have come up with something pretty simply yet valid imo.
Three basic metrics in regards to Guns -
Ballistic Rating (The difficulty in which the given ammo is to aim with in combination with lethality)
Ammo Quantity VisibilityOf these three they are weighted based on my perceived gauge of their importance in a total of 10 parts and are as follows:
Ballistic Rating: 5 parts
Ammo Quantity: 3 parts
Visibility: 2 parts
So with 10 parts, ballistic rating is worth 50% of the weight, ammo quantity 30% of the weight, visibility 20% of the weight. If these can be agreed upon then we can move on to next step.
Now we have to rate each of the previous 3 with a rank of 1 to 10, 1 being the absolute worse, 10 being the absolute best. And we then take the ratio of their score out of 10 divided by 10 for their Ranked Ratio.
Now to calculate an airplane's ballistic score you apply in following equation: (Ballistic Ratio)^(Ballistic Ranked Ratio) + (Ammo Quantity Ratio)^(Ammo Quantity Ranked Ratio) + (Visilibilty)^(Visibility Ranked Ratio)
We now need to determine what our Base 1.0 aircraft is. I believe this to be the P51D. This is how I rank it: 8 of 10 for ballistic, 8 of 10 for quantity 9 of 10 for visibility
Net Score = (5/10)^(8/10) + (3/10)^(8/10) + (2/10)^(9/10) = 1.19
All other planes ratios are taken off of this 1.19
So for the K4 I rank it: 5 of 10 for ballistic, 7 of 10 for quantity, 7 of 10 for visibility
Net Score = (5/10)^(5/10) + (3/10)^(7/10) + (3/10)^(7/10) = 1.46
Now Take Ratio of Base Aircraft/Test Aircraft = 1.19/1.46 = 0.814
Now take 0.814 reduction of the Bf109K4 from the X and Y axis of Dtango's chart to "correct" its performance based on ballistics.
This can be done for all aircraft and will be pretty accurate if we can agree on reasonable ranked values for each aircraft. The most sensitive inputs will be the ranked inputs of the P51D if it is playing the role of our Base Aircraft as well as the weighted ranked of the three metrics I described at the beginning of this post.
Another example: Tempest would rank 10 for ballistic rating, 10 for visibility and 8 for ammo quantity. Its base rating is 1.08. 1.19/1.08 = 1.1 which is then multipled to the X and Y axis and Tempest becomes 10% "more easy".
P38: 9 for ballistic rating, 9 for visibility, 10 for ammo quantity, Ratio = 1.11
Ta152: 6 for ballistic rating, 8 for visibility, 10 for ammo quantity, Ratio = 0.963
The adjustments relative to the metrics on the axis are a little too high though so perhaps cutting them in half would adjust more reasonable. So the K4 instead of a .81 ratio has a 1-((1-.81)/2)=0.905
Tempest 1.05 instead of 1.11, etc.