I also expect that we'll see a "Tales From The Yawning Portal 2" sooner rather than later- I get the impression that it sold really well, and it seems like it gives the behind the scenes crew a bit of a break in terms of effort expended putting it together.
I don't know if this would be good or bad for a TftYP, but classic adventures all from the same setting packaged in a reprint form could introduce new players to other settings without WotC devoting an entire adventure to it. D&D has a great history so a lightly modified reprint with a blurb about the adventure to provide context and background (like the Shannon Applecline write-ups on dndclassics. I use those to influence my purchases of products I'm marginally interested in)
For example, include 6-7 adventures from al-Qadim. Maybe update some of the DL series adventures to 5e (D&D's first AP!). 5e seems like enough of a success they could do a standard FR AP and then a "something else" for the other hard back adventure. There's so much history with D&D I think you could develop a lot of hype (hopefully positive!) by teasing the "something else" adventure for a few months.
Oh, heck. What I want is an adventure set in Karameikos where you get to kill Bargle. It'd definitely be an "inspired by" adventure rather than a remake.