1" is pretty normal sliding ring diameter Brian, in fact the factory rods are thinner at 0.926"
As for length, that too is pretty standard on 13' rods (18.5" - 20"). I did turn the 18"s of cork before I knew what I was doing to trim it off at the ends so it can be shortened for the customer if desired, that's easier than lengthening it.
If I were to drop in a fixed reel seat (5"s) with a rear grip of 6"s that would leave the fore grip of 9"s, not all out of place for a float rod.
And yes, shorter rear grips are definitely the way to go, nothing should stick out beyond your elbow.