PH Values

No doubt different pH values will affect different mouths in different ways. It's really going to vary from blend to blend, so pH values of different component tobaccos will probably be less useful to you than just trying a blend and seeing how it affects your mouth.

From "The Significance of pH in Tobacco and Tobacco Smoke" by D.E. Creighton (1987)
pH values
Virginia = 5.45

Burley = 5.8

Oriental = 4.9

Maryland = 6.6
Cigar Smoke = 8-8.5

Virginia Cigarette Smoke= 4.5-5.5
Keep in mind the pH scale is logarithmic so if you had a pH of 6 and increased it to a pH of 7 the "strength" has increased 10x. if you go from a pH of 6 to 8 you've increased the "strength" ( for lack of a better word) 100x
As you go up the pH scale the nicotine's free base percentage increases. So the nicotine in a cigar (with high pH) is absorbed much more readily than a cigarette with a low pH. That's why cigarette smokers have to inhale. The low pH of the tobacco binds most of the nicotine from being absorbed. Once the smoke hits the lungs the pH changes, freeing up the nicotine.
Also keep in mind that tobaccos are sauced so that would change the pH too. Even cigars are subject to sauces.

+1 Jitter, and according to Mark Ryan at his perique factory, perique actually doesn’t have a lot of nicotine. It’s a moderate Burley, and the process of making perique lowers it even more. But, because Virginias actually have a lot of nicotine, but PH lowers how much of it you absorb, a VaPer is actuallystronger because the new chemical compounds created from the nicotine in perique makes the existing nicotine in the Virginia more absorbable.

You don't often see pipe blends or other tobacco products featuring high-PH Maryland tobacco, though it may be in blends as something else. Seems as if Maryland leaf would have its own niche.