Just to follow up/confirm, yeah, Black Panther 2 will be 2021 at the earliest. Coogler is currently prepping a smaller drama for late 2019 it sounds like, and then likely won't shoot Black Panther 2 until sometime in 2020. Black Widow and The Eternals are the only other MCU movies with directors officially attached, and I don't even know if Scott Derrickson has been officially conformed for Doctor Strange 2 yet.
Marvel currently has release dates secured through 2022, so to add just a bit more context to your list, I'd guess (and just to be clear, ONLY these dates have been officially announced, not the titles)...
2020
05.01 - Black Widow
07.31 - The Eternals
11.06 - Doctor Strange 2
2021
02.12 - Black Panther 2
05.07 - Guardians of the Galaxy Vol. 3
11.05 - ???
2022
02.18 - ???
05.06 - ???
07.29 - ???
What else could fill those slots? Captain Marvel 2, of course. Speaking of, the all-female team-up will likely fill one of those spots as well. What about a third Spider-Man movie? A fifth/new-look Avengers movie in 2022? Does Hemsworth come back for a fourth Thor? Does Bucky pick up Capt's shield? Does Flacon join him? And which of these - or others - will get limited series orders for the streaming service instead of theatrical releases (right now only Loki and Scarlett Witch limited series have been announced, likely for 2020-ish)?
To answer your question, though, I'll be honest, post Spider-Man: Far From Home in July, nothing really excites me save for Guardians 3. I'm sure Marvel will obviously continue to make solid films, and I'll be there opening weekend for every single one of them, but no actors/characters on that 2020 and beyond slate, save for Peter Parker and the Guardians, really do anything for me. And Marvel no-doubt has plenty of out-of-left-field announcements still to come, and those will assuredly make for great movies/characters as well, but I just don't know if they'll ever be able to recapture the charm, charisma, and overall like-ability of the Downey/Evans/Hemsworth/Ruffalo/et al. combo ever again.