Parmandur
Book-Friend, he/him
Radiant Citadel stuff was all on other worlds, but two Candlekeep Mysteries remain in Candlekeep proper.Honestly hoping for that!
I think, IIRC, one of the Radiant Citadel ones took place at the Citadel. Either that, or the RC bit had its own adventure. Basically the same thing. But yeah, Yawning Portal is far more a feature in Dungeon of the Mad Mage than it is in Yawning Portal - though I think that was because it WAS for that adventure, but "didn't fit". So they used it as an intro to an anthology. While I don't think that ever worked very well, the basic concept of a reprint-anthology was good enough to carry that book to success.
Indeed, although I think @Parmandur has it right - the Essentials material, the DLCs, a few extras, and a short sequel that solves the mystery of the Forge. You'd have... chef's kiss.
Edit: Oh, and don't make the early encounters harder! Geez!
Aside from Yawning Portal, which was about nothing burger joke of a link because they were anticipating the Wayerdeep film from Warner Bros that fell through (hence also everything in the Waterdeep adventures, and putting Xanathar on the Everything book), I've always thought it would be fun to mix those frmae stories: have the Golden Vault operate out of the radiant Citadel, move Candlekeep and the Noble Genie dude to the Citadel...