I will repeat my thoughts on it that are bit buried in this thread.
I like a lot of what it is trying to do. I really do. Only real reason I do not champion it more over Pathfinder is I feel like I have more tools to work with in Pathfinder to help me run the types of campaigns I want to run.
I've moved over Pathfinder stuff - particularly that one questline where you're supposed to bring civilization to a wild land. Hell, I've seen a brilliant method of porting in the Planescape factions from AD&D2e - as character backgrounds, something already organic to D&D5e!
I'll admit, I wanted to keep playing Pathfinder if only to keep Paizo going, support the underdog, ya know? But man... D&D5e is just so much better IMHO. Well thought out. Just when I think that there ISN'T a rule for something, or a player asks me, "Can I do that?" I find a rule.
Speaking of Planescape... I ran a GREAT little Planescape campaign in 5e a few months ago, with only one sore spot: The barbarian player who used mud dice without filling in the numbers so he could 'fudge' his rolls to whatever he needed.
At least, the players thought it was great; me, I felt almost like I was chugging them along the plot train too hard, but apparently I really brought to life Acheron and the Grey Wastes for them.
I started it simply: "There's an old saying among elves that adventurer and fool are two words for the same thing. You proved it true not five minutes ago, when you saw the arch - that legends say opened up a gateway once every fifty years to a city of unimaginable weath - light up and stepped through it..."
And I had them
freaking out about the Grey Wastes draining their memories away. "I need you all to close your eyes and think about the first time you fell in love, because that is what your characters are dreaming of tonight. *pause for about five seconds* Remember that pure, burning feeling? That sublime, unrequited passion? As you toss and turn, you realize that it meant
nothing. One of the strongest memories of your life... was worthless. And now, it is gone. Who was it that you first fell in love with? As you open your eyes,
you don't know, and you look down to see that a little bit of the color in your skin is gone."
Three of them actually looked down at their hands at that moment. It was... a good GM moment.
Really looking forward to Xanathar's Guide to Everything. I hope that some of the subclasses they've been putting out in Unearthed Arcana are made official in it - and I also hope that some of those subclasses never see the light of day. Favored Soul? Want to see as a 'clerical sorcerer' which
is what it always was. That peacemonger paladin? Kill it with fire, it has inter-party conflict written all over it with its obsession with capturing enemies.