Why would the Germans add a third Luftflotte in Southern France, since the number of strategic theaters hasn't changed radically compared to OTL (eastern border, Norway, western Europe, Mediterranean). If the Germans had so many unemployed planes and pilots available, why didn't they use them in OTL to finish the RAF ?

Sorry Russ, but I can't see the LW having a field day during the last days of the BoF and during the BoB, with less planes and pilots and more opponents !
Around 15 August (see appendix 40-8-1), the AdA has :
- around 900 fighters (nearly 590 modern and 280 semi-modern ones, counting MS-406 in the later category)
- around 780 bombers (650 modern, 22 semi-modern)
- 60 attack planes
- over 500 recce planes
This means the RAF can keep home some Sqn instead of sending them to the Med. The French could even send plane to GB.