I've been trying to push up into the +15 range and it's only at this point that I'm really starting to feel like my ilvl (389 Resto Druid) is starting to struggle to keep up. I'm sure if I had a static team it would be a lot more feasible, but PUGs are pretty rough. The only 15 I've tried so far was a Vault this week and we didn't time the key since I wasn't really prepared. A few wipes on boss 2 and 3 before I figured out how to heal through them. Since I'm basically at the low end of normal raid ilvl it does make sense that the higher keys are a little too far out of reach without a well coordinated team. I'm not sure how much this is because of the affixes this week though, we shall see when it swaps back to fortified.

The only thing I find weird is that there is basically a wall at 10-13 where the ilvl from end of dungeon doesn't increase but the dungeons keep getting harder and harder. At this point I only have 4 items less than 392 so it's either push into and farm 14 (for 3 ilvl upgrades, feels inefficient time wise) or try to do 15s which I feel like I'm not prepared to PUG yet and would probably brick a lot of keys. My guess is that the design intent is to be stuck here and wait for great vaults/valor to get to the point where 15+ becomes more feasible to farm later in the season.