For lair bosses you don't really need to get all the way to 100 to phase them once you have decent damage, they're squishy.
Ended up making a random pair of legendary gloves this morning (no GA's, just all damage mods) to try instead of my gohrs and my damage went from lots of 3 digit billions to lots of 4 digit billions. Not having the suck was kinda noticeable in the one 130 pit I just did, though. Problem is, I think i've looted probably 10553880738 pairs of unique gloves at this point and can't get decent rolls. Doesn't help that it seems like only about 10% of gloves are Gohrs and the other 90% are the two shit pairs that ww doesn't use.
Only challenges I have left on the season stuff are like 9 more nightmare dungeons (trying to finish maxing my warplans though so haven't just knocked em out), crafting the stupid horadric and flawless horadric gems, and t12 lillith.