My current approach is that I am not worried about matching or carrying around Doffs etc....

What I am doing is converting all "bound" Doffs to ones I can sell, grind or stick in the mail. I am sure many people have lots of green or even blue doffs bound that they cant do a lot with. The exchanges are perfect for trading and converting them to unlocked Doff. Also using some suppot reward doffs that I might have too many off.

I then save the white or green exchange rewards for future exchanges once I cleen out all the bound doffs mucking up my roster. And sometimes the RNG god smiles on you and you get a blue or purple!