Bungie says that they nerf weapons based on popularity. Using that logic, they should buff the Defender based on its rarity in the Crucible. They don't even have to do anything major, they just need to improve the defender neutral game so that it's as good as other titan subclasses. For example, strikers and sunbreakers have extra damage on their melee attacks when their ability is charged, but defenders don't. Meanwhile, sunsingers gain a shield on melee hit, while defenders need a kill. If they buffed defender melee damage, or altered force barrier to activate on hit, it would make defenders better in the neutral game. I also think that they should increase the bubble's strength so that every other super in the game doesn't completely nullify it, especially since they've all been buffed while the bubble is completely unchanged.

Support class doesn't need to be built around pvp. It's good enough if you play smart.