If the gear was made taller then this may have been an issue with the front air stairs not being long enough to reach the ground.
I suppose anything is possible, but it's a bit difficult to imagine engineers saying, "We can't lengthen the main gear, because the (optional/aftermarket) airstairs wouldn't be long enough. Let's move the engines, significantly changing the aerodynamics of the airplane, and play around with an add-on to STS."