How long do you reckon this DLC will stay up? I've unlocked most of the armour cosmetics, which I've applied to my character as it adds a nice touch.
I do often do runs one after another, usually return to orbit once I collect my loot though, I don't think it requires staying for the timer to count down to 0 to count towards the bonus xp. My favourite end fight so far is the Cabal, love the open area and just slashing through everyone. Hardest is probably the Crota bonus round, it's very chaotic and staying alive can be a challenge.