If you are on a PC, you don't even need mods. Just open the folder where your characters are saved, make a sub folder with the character's name or what have you and put characters you aren't currently playing and all their auto and quick saves in it. Just keep the character you are currently playing in the main folder. You can even switch on the fly by tabbing out of the game, moving your current character into it's save folder, and pulling the files for the character you want to play out of their folder into the main save folder.
Seems like a pain in the ass when it would take minimal effort to incorporate into the game, proven by the mods already available for it on PC.
Yes every new game character should have there own page dedicated to that characters saves. I would like to know the technical reasons as to why this can't be done on the likes of consoles.
There are none, although many consoles have less space then PC, so having their own quicksaves and autosaves might take up too much space.