Congratulations! You got yourself a fine revolver.
I did the same thing this past Friday adding a 2.25" SP101 to my growing Ruger collection of GP100's.
I will soon replace the front sight with a fiber optic one so that I can better align my aiming point. Other than that, the SP101 design is exceptionally sturdy and well-balanced which makes other modifications unecessary.
Good luck and safe shooting with your new Ruger.