Again, for the kind of shooting you are doing, obviously, the ballistic programs you are using do the job for you, and that is great. If I was only shooting out to 1,000 yards, I could manage quite nicely on big game using the same programs that you do. Small varmints at such distances and beyond, however, are another matter entirely. Some of the varmints I shoot have a vital area that is only about 1.5-2" across, and on these, at these distances, a 1/8' error can give you a complete miss. I do a great deal of shooting, and keep detailed records on every shot I take, so that I can hit the varmints I want to, at the ranges, and under the conditions, I want to hit them. No ballistic program that I have yet seen gives precise enough data to be of more than ballpark use for this, although for that, they work just fine.
Good luck, and good shooting!