You definitely want Fw 190As defending the Reich. Make sure they are at full strength and about 75% experience.
As for fighter-bombers, the Bf-110s are very effective when there are no defending escort fighters, however they still suffer a high degree of attrition. However the Fw-190Fs are actually pretty good.
Forget the Bf-109s, both Fs and Gs.
At the beginning I usually place one or two squadrons in the OKW HQ and one in the Italian Front HQ. The range of the aircraft in these two front is 20 hexes, regardless of their stated range.
In addition, you may want to place one normal HQ (usually the Hungarian HQ) within 7 hexes of Budapet, and another one (a Romanian one) in Romania, within 7 hexes of Bucharest and Ploesti. Each HQ with one squadron.
Make a note that any air unit in the Western and Italian Front HQs will suffer attrition, in addition to that of combat.
By 1944, you may want to increase the squadrons by one in each of the HQs.