Thanks for doing this, I can only imagine how much time this must have taken. I wish there was a way to +1 suggestions so that we could tell what has the biggest consensus in this list and build a community-based order of priority, but agree with GM4Him that most of those are great !
Personally not a fan of a 5 or 6 member party, but there are so many people asking for it that I'll bow to the majority's opinion. I just don't see this happening given the current state of development... Hope I'm wrong.
Thanks for giving a voice to us poor rogues who want to have a bit more value

(Cunning Action + Expertise + Auto-sneak attack).
Is there a way we could add this to the mega thread section ?
Totally agree! My poor Rogues! Their Expertise is gone, anyone can drink potions as a Bonus so Fast Hands is now not as good, Cunning Action is not as good too because anyone can Hide as a Bonus (at least Disengage is now an Action so Rogues get the Bonus Action Disengage and Dash... though they can REALLY Dash now because of this)... but mainly the Expertise!!! Make the Rogues special again in some way, at least! Please!
I'd prioritize Movement Mechanics, Inventory Management and UI first, personally. I spend more time accidentally clicking on things, including party members, managing tons and tons of items in inventory, and I am always arranging and rearranging my hotbar otherwise I can't find the special moves I'm trying to use like off hand attack or Menacing Strike Melee or one of my more important spells. Constant micro-managing of everything is really wearing the game down.
As much as I'd LOVE things like Day/Night and Party of 6, the game would be much more fun with some basic redesign of these three elements.