That's completely illogical.
No it's not, and you missed my point.
16% increases in every stat might produce more than a 16% overall increase in utility, yes. But a 16% increase in performance
shouldn't (barring considerations like "well, you need only one of them instead of 1 1/6 of them").
What's being looked at here is the increases in effectiveness: i.e. the quadrupling you refer to. That's the stage being considered (not the raw stats). And at that stage, being 16% better at everything doesn't somehow make something more than 16% more valuable.
If Unit A produces 1.0 hits and takes 1.0 hits to kill, and Unit B produces 2.0 hits and takes 2.0 hits to kill, Unit B is logically worth twice as much as Unit A.
A Storm Talon will produce 1 1/6 hits, vs 1 hit for a Thunderbolt. It can take 1 1/3 hits, vs 1 1/6 for a Thunderbolt.
That's a 17% increase and a 14% increase, respectively.
The increase in initiative may indeed create the effect you suggest, however. As might an increase in speed/maneuverability.
So doubling every value will not double the value but, restricting us to hits and losses, will be worth 8 times.
See, that's just wrong
Let's say Unit A produces 1.0 hits and takes 1.0 hits to kill. Unit C produces 4.0 (quadrupling, as you say) and takes 2.0 (doubling, as you say) to kill.
It's not worth eight times what Unit A is. It can kill as much as 4 As, and take as much damage as 2. So (assuming other factors are equal), it's worth between twice and four times as much as A.