PE-2's numbers (range and speed) are with internal bombs which are limited to six 220lb bombs. The bigger bombs ( like 550lb) are carried externally. While this adds to the flexibility it also means that both speed and range are not what the stats say when carrying the larger bombs.
True, Pe-2 was however able to successfully conduct some fairly long distance raids early in the war against various targets such as the Ploesti oil fields and German shipping in the Baltic. If you put an R-2600 (or say, an Ah-82) into it maybe it could carry more bombs and still fly faster (though you'd probably need to find a place to put some more fuel). I would love to know what the speed of the (non-speculative) aircraft was with external ordinance. Regardless, it's always still helpful to have that speed to run-away with after the bombs are dropped.
Early B-25s held 652 gallons in the wings, during the B-25C & D production run aux wing tanks were added that held 300 gallons. Then you had various tanks that fit into bomb bay or into the waist of the plane behind the bomb bay.
The Baltimore falls in between the A-20 and the B-25 and was a tail dragger. No US large bomber after the B-23 used a tail wheel except the Ventura and since that was a modified version of the Super Electra/ Hudson/Loadstar it inherited the tail gear.
Being a tail-dragger no doubt contributed to the tricky takeoff handling. But lets not forget that the B-17 was also a tail dragger. However I do think that if they found it tricky to take off from nice grass fields in England or desert fields in Egypt, assigning green crews to Baltimores and making them take off from Henderson field or Port Moreseby would be rather cruel.
Douglas also started work on the A-26 in late 1940 which might have also influenced the US lack of Interest in the Baltimore.
Also a good point! Too bad it took them so long to get into action...