[Aymar_Mauri]

What would be the difference between a A-4 from 1943 and a A-5? I mean: If a A-4 from 1943 is essentially a A-5, why not skip the A-4 and make the A-5 instead?

IIRC the difference between a 1942 A-3 and A-4 are the loadout options, so why not make a A-4 with same performance as A-3 but increased loadouts (Jabo, Schlachtflugzeug).
Then make a A-5 with the performance of 1943.

Disagree entirelly. The A5 is also necessary due to physical differences in the chassis/fuselage. These differences were necessary to change the CoG to increase the variety and type of loadouts. Also the A4 was the first really widespread version in use. We can't compromisse if we want historical accuracy.

So:

A3 (no loadouts) > A4 (basic external loadouts) > A5 (more extensive external loadouts).

All of those existing made by Oleg need new slot versions. All are necessary including the ones we don't have like the F3, F9 and a couple more representative of the G series.