funny, the A5 seems to gun down ords and radar just fine! and its fast too!
The A5 accelerates well at low altitude, but I wouldnt call it "fast." Especially considering that the in-game version is slower than its real-life version by a margin significant enough to affect potency against 1944+ A/C.
Oak - I cant speak for HTC, but I believe that specific varients were chosen to best represent that aircraft during a specific time period - to fill in the time gaps, so to speak.
The 109 set is the best example. The E-4 was the most significant Emil. The F-4 was the most significant Frederick, the G-6 was the most significant Gustav (and probably the most significant 109, period), the G-2 and G-14 represent the early and late Gustav line, on either side of the G-6, and the K4 represents the last effort.
All your bases are covered. I would guess that the issue with adding another 190 Anton is that the A5 fills the early-war gap well enough, already, for no extra work.
Earlier versions would probably end up as scenario-only hanger-queens and later A's would likely not show an appreciable performance differential when compared to the A5. In both cases, however, the amount of work required to take the aircraft from concept to your monitor is huge - and for what gain?
That said... bring the 190A-9 to Aces High!

(And give me my 12MPH back).