I'll just throw in my 2 motes.
The end game in The Taken King is missing three crucial things from year one - challenge, gear chase, and payoff.
Challenge: When you hit light 300 (which is not that difficult if you've raided a few times), you are overleveled for everything in the game except the Raid. In Year One, most of the content was at max level, so reaching Level 30 was desirable to benefit from the damage resistance. In Year Two however, Weekly Strikes and Daily story missions are not max level. The only encounter we are leveling up for is Hard Mode. This means that if you do not run the Raid, there is no reason to hit the level cap; consequently, there is no reason to organize a group run the Raid with.
Gear Chase: We used to share checkpoints for weapon drops - that's how coveted weapons from Year One were. Take away their elements and they are still coveted because their base stats were really fucking good - absolutely too good, but that's why the content was replayed as much as it was. Vault of Glass in itself is fun, but it's not 12 months worth of replayability fun without the weapons that were part of it and the stories of obtaining them. Almost every weapon was worth getting from that Raid.
We are running the most difficult content over and over because we want the best guns in the game. We want the best guns to feel powerful and get ready for the next challenge. We celebrate those moments when RNG blesses us with what we want, and throw ourselves into the dark corners of time when it doesn't. That equates to replay value week after week by our own volition - not through arbitrary time gates - and we know that the reward is worth it because the guns are fucking amazing.
Why level up for the most difficult content to run the most difficult content for guns that are not amazing? The satisfaction of beating Oryx dissipates when you open the chest week after week and either find nothing or a weapon that may as well be a doorstopper.
There can still be good weapons in the game without trivializing the encounters - certainly not anymore than they already are by being overleveled. A well designed and mechanically intensive encounter is not going to fall apart when we bring good weapons to the battle. Our good weapons are going to make the encounter more fun because we feel powerful after putting in the work to get there.
Payoff: And that's the root of these problems. The work we put in is disproportionate to what we're getting out of it. Destiny needs something that makes players hungry. It does not need exotic quests that roll out every week for one day only before disappearing again. It does not need lengthy quests that reward the player with a gun they'll use once. And it absolutely does not need less of the materials to upgrade the weapons when we want to try them out.
Variety is an illusion because people will always seek the best guns; Destiny does not need variety, because that gives the player too many choices and consequentially introduces mediocrity when those choices are distilled to be balanced similarly to one another. What is the difference between Vendor weapons and Raid weapons? One looks like a slab of meat, and the other is something you actually use.
Destiny needs direction and it needs focus. Give players builds to chase after and then make the content difficult as fuck so that those builds are way more desirable. I want to see Oryx drop the most bad ass Solar hand cannon, and then level 42 Nightfall with Solar Burn every other week. Boom, now people are replaying the Raid because they want to blow through that Nightfall.
In laymen's terms, removing elemental damage from weapons dropping from the most difficult content in the game (and by extension, making the base stats on those weapons complete trash) is almost single-handedly responsible for the problem with the end game. The other problem is again - the payoff of running the Raid, seeing gear drop that isn't your level, and feeling like you wasted time when you realized you were chasing after something you don't even need.
At the end of the day, we're using guns, not armor. It's more fun to shoot an OP gun than it is to wear stronger armor.
Luke, I've disagreed with your philosophy for Year Two ever since I got the Touch of Malice and realized that it was only worth using for 5 minutes a week. I hope the team reconsiders these decisions, otherwise I can't see Year Two's longevity coming anywhere close to that of Year One. It hasn't for me.
Perhaps we are no longer chasing after max level and strong builds because there is no longer an expansion with more difficult content on the horizon. But I wouldn't imagine that Bungie would want to design the game to encourage players to play it less than they did before, because that's exactly what The Taken King is doing.
Also, I play Halo on Heroic when I want to enjoy myself and Legendary when I want to be a masochist. If you guys think being underleveled in Destiny is bad, play Halo 2 on Legendary.