Imo, the reason any of this is even much of an issue is the ongoing, overall lack of content. I think that if the dlc had come with more new content worth rehashing endlessly, and opened up more customization (weps, armor, etc.) options rather than just replacing the old ones, then it likely wouldn't have mattered that Vog became relatively obsolete. If they're not going to give us a wide range of new activities per dlc, then they really need to avoid devaluing earlier content. If each dlc is going to shoehorn high lvl guardians into one new little sandbox, then do as others have suggested, and open up new level challenges, with higher rated drops, on old content (while requiring newest dlc for expanded levels) so we can continue to enjoy the game as a whole, rather than just the latest appetizer. Tl;dr - increase dlc content or give vets w/newest dlc higher lvl versions of old activities