I’ve come to the conclusion that it is one of the things that I really would like to change from the core game.
The only way to farm it (that I know off) is trading money and weapons with a friend, which gets pretty boring.
So I have a simple offer for you the modders of the comunity: you make a patch reworking the system to be more like the Paragon of Diablo 3 or Omega from marvel heroes and Grim Dawn.
And I will pay you for your work. It can be later updated to Nexus forums for everyone to enjoy if you agree to it.
Here are my ideas (I have a bunch of them since I know some of them are impossible/very hard to code)
Add an experience system, like in Diablo 3. Your experience past level 72 goes directly to your Badass bar this could replace the challenges. Probably earning more do the higher your Badass rank is.
(This, I assume would would be the most difficult to pull of, however it would be great)
Make the challenges not give you flat bonuses that get useless after not much time, instead of 1,5,10,50,100. It could be 1%,5%,10%50%75%of your Badass bar, that would allow you to grind faster.
If the previous options are too complicated just change the flat values of rewards
Any of those changes would require some changes in the UI, but I don’t think it would be a major problem.
If any of you is up to it just hit me up via a reply or pm.
We can discuss your payment and the balance later.