Honestly, I don't see how you DON'T do a Sinister Six movie, now. We have a competent writing team, a STRONG supporting cast that feature more than 2 people (looking at you, Amazing Spider-man 1 and 2), and you have a rich universe in which to drop them all. Add in the twist at the end of Far From Home, and you have the perfect catalyst!
Personally, I would love to see a Spider-Man 3 where he is hunted by a half-Wakandan Kraven the Hunter after his outing in FFH sends him underground. Kraven threatens, kidpnaps, and imprisons his loved ones, only for Spider-Man to defeat him, and realize that his loved ones will never cease being in danger until he can find a way to live public, or unring the bell, as it were.
He then turns to Doctor Strange, who teams with Reed Richards (LET ME DREAM) to wipe all tech and memories of everyone who learned he was Spider-Man from Mysterio's outing. Strange warns of the consequences of such a decision, but they do it anyway because, well, comics. Peter awakens to see that it worked, but that there was an escapee from Ryker's...the Vulture. Apparently, the fix didn't undo anyone's knowledge from before. Everyone remembers him being outed, but not who he was underneath. The Vulture gets free and rallies some troops with the help of a mysterious benefactor, and the film goes from there.
My 6:
1) Doc Ock (THE ONLY FITTING MASTERMIND)
2) Shocker (Full suit, this time)
3) Mysterio (with an Edith-lite satellite hijacked by Doc Ock to aid in their quest...maybe make Mysterio be used by Ock for something bigger. I don't know, not a writer)
4) Kraven
5) Scorpion
6) Vulture