Pro front coilovers are 1" taller. Rear is the same on all of them.
All models share very similar frames with the same cross member that is the low point in the front - where you measured. A 1" lift in front would result in the same ground clearance as a TRD Pro.
On IFS the lift does change the static ride height - meaning more ground clearance as measured at the skid.
A typical lift that does not change the control arms or the mounting points (not long travel or bracket lift) does not change tire fitment size on IFS. If it fits with a 3" lift - it also fits stock height.
With about a 2" lift and 33" tires I have about 12.5 inches at the front skid. It's lower by at least 1 inch at the the differential skid behind the engine skid where they are all the lowest point up front. I don't know exactly what the measurement is there. Just to give you an idea of what type of clearance gain you might find from some fairly mild lift options. You can see why so many of us put a small lift on. Also you can see in the second picture that the rear differential ends up as the low point pretty quickly.