I'm also a big fan of the Dalelands for all of the listed reasons! And for many years now, Myth Drannor has been something I've wanted to use in a campaign, but I felt the Ruins of Myth Drannor lacked details for me as a DM to run. It had tons of details, but a lot of it was focused on the groups around Myth Drannor - good info but not enough to prep the feel of the city itself.
But the idea stuck in my head for many years. I know Myth Drannor was restored during the D&D 4th Edition era, but then during the Sundering the City of Shade floated over from the Anauroch and crashed into it. This bit of details, tantalizingly small from the Sword Coast Adventurers Guide, was enough for me to want to dig into it more. So I did! I just finished writing up a Myth Drannor supplement for DMsGuild that provides details, magic, and monsters for using the now shadow-filled ruins of Myth Drannor in a campaign. I've got 20 power groups with their interests laid out in the city, and a map with hexes for exploration. I use the Journey rules from the DMG with encounters and flavor text, and I've got a Danger Rating system for escalating tension in the ruins. Here's the map I worked up in Inkarnate for it!
I'm hoping to get this supplement out by the end of the year, but I want to put my paws on the new Forgotten Realms book to adjust to any new or changed lore for the Myth Drannor region. I think the timeline moves up to 1501 DR for the new books too, so I want to accommodate that.