Baer, forsure. You can't look at total kills (too many easy kills to be had in Russia early in the war), you can't look at kills to sorties ratio either (the highest in the LW was some guy, I don't have my books at hand right now for his name, who had something like 75 sorties and close to that in kills. But all that proves was he was hot for a month or two). You want a guy who has fought vs all the allies and done well, fought on all or most fronts and done well.....That is Baer.
You want a guy who started and ended the war, he did that also. Here is his stats that I quickly just grabbed of the net.
He fought on the : Western Front, Eastern Front, Mediterranean
ASSIGNED COMBAT AIRCRAFT:
Messerschmitt Bf 109E/F/G
Focke-Wulf Fw 190A-7/A-8
Messerschmitt Me 262A-1a
AWARDS:
Ritterkreuz des Eisernen Kreuzes mit Eichenlaub und Schwertern
(Knights Cross of the Iron Cross with Oak Leaves and Swords)
VICTORIES:
220 Aerial Destroyed
59 Western Front
96 Eastern Front
65 Mediterranean Front
1000+ Combat Sorties
So he shot down 124 western planes and 96 Russian planes. (including 16 kills in a jet)
He was a warrior of the top level by anyone's standards and IMHO (and many others) he was the best of the best from WW2 (either Axis or Allied).