I've used mules on a second profile, split screen, since the game came out and I've had no problem with BA rank being reset. Just make sure you exit the game with the mule first by saving before exiting and saving with the main profile character.
I don't think collecting a bunch of nice weapons you worked hard to find is hoarding. Hoarding is the excessive collecting of items with the inability to discard any of them. For me, anyway, as soon as I find a better version of something I have, I sell it.
The developers who boast having a bajillion guns in the game should have factored in more inventory space. Little Gaige can run around the world with up to 4 weapons, 4 accessories, and 27 items strapped to her back, but she can only store up to 16 items in that big safe at HQ. Doesn't make any sense.
- - - If the phone don't ring, you'll know it's me.
^ This plus people may want to trade or give items that are not useful to themselves but to others. Also with 5 classes in game you may want to keep rare stuff you find for other classes if decide to start using them.
Honestly outside of items that have red text/orange items, I don't save weapons/items and usually sell them just for the fact that they never give a bank/storage that has a decent size space. I don't feel like using mule characters to store other items on.
GT: Boomer and Tank Pretty darn confident..... I don't want to have to wait till the Microendony XBOXS 4ii comes out another 15 years later....