The .45 Colt is very versitile in a revolver/lever rifle combo and so is the .357 Magnum and .44 Magnum. I wouldn't use the Taurus Judge as a pistol though, its just a gimmick and .410 is more or less worthless for anything but small game at close ranges. Just stick with a Ruger or even a Smith and Wesson revolver and you will much happier and have a much more durable weapon. I say the perfect combo in that caliber is the Rossi 16" M92 in stainless with a stainless Ruger Vaquero, that would be a virtually indestructable pair.
My personal preference for a simple scavaging/survival is the .357 Magnum combo, I have the Marlin 1894CSS and Ruger GP100. Its a more common round with more modern weapons available and it can kill anything I need it to in my neck of the woods. Its also easy and cheap to reload for and both guns can handle a wide range of power levels and bullet weights. You could even cast your own bullets from wheel weights and pull powder and primers from other pistol rounds you find around if you had to. You could keep a rifle and handgun like that running for years after most of the ammo was gone and both could still maintain a higher firing rate and range than the single shot shotguns and random weapons you might run into.
But, I would probably never have to do this if the SHTF because I have a shitload of 5.56 and 9mm I would have to go through before I would have to rely on those weapons for everything. For now, they are just fun guns that are cheap to shoot.
When you try to make one tool that does everything, you end up with a tool that's shitty at everything. This is more true of firearms than perhaps anything else. In general, the more complex the tool, the less effective it will be to attempt to multi-task with it.
A pistol is a pistol, a rifle is a rifle, a shotgun is a shotgun. Making them all the same caliber (such as .45 LC/.410) generally means you end up with a shitty, heavy recoil, heavy pistol, a shitty, low power rifle, and a shitty, low power shotgun.
While I do generally agree with the idea of getting the right tool for the job (I believe in the survival battery) and there is no "perfect do-it-all" rifle, I have to say that the .45 Colt, .44 Magnum, and .357 Magnum cartridges get about as close as it gets to a successful version of this concept. I also disagree with you about the .45 Colt lever action bieng a "shitty, low power rifle." That is just simply not true unless you are using cowboy action loads or something. The modern Rossi/Puma M92 lever action carbine can handle extreme pressures (the handle .454 Casull and .44 Magnum just fine ) and very hot .45 Colt with ease making it quite a powerful and effective rifle. It certainly exceeds the power and destructive power of the 5.56X45 by a long shot, so is that a "shitty, low-power rifle"?
Just spend a minute reading this if you want to see what it can do...http://www.leverguns.com/articles/paco/ ... vergun.htm
My father has been reloading for his M92's and Ruger Vaquero's in .45 Colt for years and he has found the same to be true, I've seen the power myself.