Graywolf,
I have not looked through the 1400's so I cannot comment. The optics on the 2200 and 2400 are supposed to be an upgrade, obviously they have a little more power, but I suspect the coatings might be improved as well if it is setup like the Kilo line, but I can't say for sure. I can say that the 2400 works well enough, I just came in from Coyote hunting and while not top drawer, the optics are definitely sufficient to get the job done, unlike my Kilo 850.
As to the software and how it works, yes, Sig has done their homework here, at least in our experience. I handed it to my 15 year old son. He had it loaded and setup with his ballistics and the local conditions in mere minutes. I actually gave it to him, pointed him to Sig's site and said figure it out...wanted to see how easy it would be for someone to do it cold. Easy. We then took it out a few days later, he ranged an elk, dialed the displayed solution and nailed it. No problem.
So I don't think you are going to have a problem with the software. But if you can find a deal (and I think there are a bunch out there right now), I would try and get into the 2200 if I were you. The possibility of improved optics aside, the bigger reason is that conditions really cut into ranging performance. Rain, mist, fog, snow, dust in the air, bright sun etc, or sun low in the sky...lots of things and all of a sudden, your range is 50% of what you expected. So when it comes to RF's, more horsepower. That extra horsepower also lets you range more surely to when doing it handheld. That is, as you approach the limits of what an RF can do under a particular set of conditions, how steady you are becomes much more critical. So an RF that can range to 2500 yards will more easily handle a shaky 1000 than one that can range to 1500. That RF will require much more steadyness to pull off that 1k range in my experience.
All that is to say, if you can, the extra power comes in more handy than one would think in real world use, so I would recommend buying as much as you can afford.