I'm asking this not to judge, but out of pure curiosity. Why would you want to only use one amp sim? Do you not have any way to change patches with your feet, so you want to make one patch as versatile as possible?
Because if you want three different sounds from one amp, what you're going to end up doing in the end is less "keeping the same sonic footprint" and more "making a huge compromise to every single tone you use because it has to cover so much other ground." Your clean tone will suffer because it also has to do high gain leads which require a different type of gain and eq structure, your heavy rhythm will suffer because it has to be able to clean up well so you won't be able to compress or drive it as hard as you're going to want to, etc.
What you really should do is make a couple of different patches, but create them with the other patches in mind. That way, you'll be aware of your overall sound and your patches won't be night and day changes, but you'll still have as much versatility as you'll need.
If you're using an Ultra, you have over 70 different amps, 20 different drives, 6 EQ blocks at once, and 256 patches with which to arrange those in any combination you can imagine, to be called up instantly. And you're seriously constraining that potential versatility why again?
However, having said all that, my vote goes to the VHT Deliverance for what you're looking for. It's wonderfully versatile and has a huge usable gain range. Your volume control will take you miles with that amp.