My distance from the ground is determined by the length of my legs and the need for some clearance between the ground and the pedals. I doubt that there's more than an inch difference between my bikes - and I'm not sure if I'm higher or lower on my folder. I pump up my folder tires to slightly higher pressure than in my other bikes, and the tire width is in between that of my road bike and my touring bike.

I haven't noticed much difference in the amount of water/dirt flung from the tires in wet conditions but haven't tried to make any kind of controlled experiment to compare.