It seems to me that MacArthur is more often castigated than not for his mishandling of the defense of the Philippines at the start of the Pacific War, unimpressive management of the New Guinea Campaign, inability to get along with the Navy, and for his obsessive focus on the liberation of the Philippines, not to mention a variety of poor leadership habits, including:
Playing favorites and appointing officers of questionable quality to important command positions.
Disregard of military intelligence that disagreed with his preconceived notions (invasion of Luzon).
Willingness to sacrifice the lives of his own troops for public relations objectives (i.e. forbidding artillery and air bombardment during the initial stages of the Battle of Manila)
Inability to maintain popularity among his troops due to a reputation for glory-seeking
Borderline insubordination (contradicting the agenda of his own president in Korea).
My question is... there has to be a reason why he was trusted with such crucial military operations, right? He had even been tipped for supreme command of the planned invasion of the Japanese Home Islands. Surely a man who rose over the course of the war to wield such power must have had some strengths that justified his appointments?
So... did MacArthur have any strong qualities? Logistics, perhaps? Organization? I'm genuinely curious!
Well, the last one (insubordination) is why he ended up getting fired, so they can be discounted, I think. And I really don't think you can hold the artillery and air restrictions in Manilla against him. Such concerns are rightfully the purview of Generals. Those of us at lower levels know our lives are at risk anyway, we just ask that the risk is weighed by benefit.
Bottom line, he got things done. Although I am a believer that the MacArthur or Patton schools of leadership belong in the museum, you can't really deny that they achieved results.
His personal valor is, I think beyond question, coming out of WW1 with two DSCs and seven(!) Silver Stars.
I don't think you can hold the loss of the Philippines against him. He really did believe he would get more support than he actually did, though one does wonder if he had a proper appreciation for the bigger picture. His performance as commander SWPA doesn't seem to show any unusual blemishes, but it's not my major area of knowledge. Bear in mind, though, that there was a significant international component of this command, so he had to navigate many of the same mine fields as Eisenhower had to in Europe.
Given that he was basically HMFIC in Japan for the post-war years, I don't think you can look at how Japan turned out and say that he did badly in any way.
Finally, when it came to Korea (another international op), he went from keeping a tenuous toehold in the corner of the country to practically taking over the peninsula in nothing flat. It took a lot of that famous force of will of his in order to get approval for the Inch'on landings, and he saw it executed as near to perfectly as makes no difference, and an amphibious assault is up there on the difficult military feats list.