I wouldn't call what we got in VoG "progression". More like "weekly frustration".
I think the system they're implementing now is far better. People want to look special, look different from everyone else. Having everyone run around in raid gear kinda counters that. Now, if you want to be a badass titan with a fur collar and still reach level 34, you can, and I think that's great.
Looking cool doesn't mean anything when there's nothing to do. Vault of Glass weekly raiding is what kept people around and raiding and playing the game. Progression and carrot on a stick gameplay is the life and death of this style of MMO. The problem was that the raid was too short and the content dolled out via a really oppressive RNG system. If they're going to borrow so heavily from MMOs that work like this then they should get the parts that make that system work.
Every level progression system has that point where you hit end game and have done everything and just go "now what". The problem is that that loop is too damn tiny in Destiny and with House of Wolves it's not even there anymore.
I haven't paid too close attention but the upgrading gear system seems to be connected to doing Prison of Elders. It would be nice if the currency needed to upgrade was very rare.