This league was fucking wildin'. I have a tankyish, decently mobile, high dps build and even sometimes it just isn't enough. The nerfs were 100% needed, and hopefully round 2 with aura stacking shit is good, because certain places are a nightmare.
They need to remove invuln or rework it, 100%. I had a consecrator Invuln mob and it was unkillable. You had a 2 second dps window to do more than 1/2 it's hp, BUT WAIT, it was an expedition mob with regen and block so it was nigh impossible even with 5x the dps for the lvl 71 map I'm in. Ice prison is annoying, but at least you can get out pretty easily now. Some of the stun/anti regen shit is pretty annoying. They need to find the no-no combinations for affixes and prevent them from occuring like Invuln/trickster and shit.
Sentinels are kind of hilarious. Reduced damage so explodes don't do shit for helping you clear them, but they do juice. MAN do they juice. I think Redbot is the way to go with a yellow for bosses once your DPS is pretty up there. Blue seems incredibly niche and overall just like a worse Redbot unless you've got 100+ mobs in one place on your screen or nearby which isn't happening quite yet.
Also watch out for skeleton mages. No, not the meta summoner build, the regular mobs. A white one was nuking for 5000+ fire damage with 75% fire res in Merc lab last night. I survived it with 4khp and 4k molten shell, but my guildmate with similar stats did not.