Hi,
I suggest a very simple way to adjust campaign difficulty, at character creation, you are given the choice to start the campaign on normal, +, ++ or +++ difficulty.
For each + all the campaign maps are boosted by character level time + corruption (except dungeon that should have specific boost and possibly bosses 
).
So, a level 1 character on a + campaign have a 1 corruption boosted map, a level 10 a 10 corruption boosted map.
A level 15 character on a ++ campaign have campaign maps with 30 corruption boost.
At campaign end, when player start enhanced monoliths, monolith starts with 100 times + corruption.
Now, Hardcore SSF +++ level 100 campaign would be a thing of beauty 