This is easily one of my favorite "journeys" in videogames. Loved the story, the characters, the writing, the acting, the pacing, the gameplay, the creature designs, etc. So good.
They really nailed the ending. Great closure for Seb and Lily and Kidman. Wish Myra could've escaped STEM with them, but at least Seb and Myra achieved closure and a sense of peace and Myra's sacrifice paid off.
It felt bittersweet seeing Union dissolve at the end. As horrifying as the place was, I'd grown rather fond of it as a videogame setting. I already feel some measure of nostalgia for it... But in the event of a TEW3, I'll be excited to see what new world they create.
I imagine a TEW3 would show the "wireless STEM" in action, drawing large swathes of the real world into a virtual one, without needing to connect them.
As for a protagonist, I'm not sure who it'd follow. Maybe Kidman could be lead, cleaning up loose ends. I think Joseph will factor into the TEW2 DLC, if there is any.
Seb's story is probably finished. He went from being a blank slate in TEW1 to showing the full spectrum of emotion in TEW2, with a nice character arc full of highs and lows, overcoming his guilt and fears and redeeming himself. He now has Lily back; he will stay with her and protect her. I don't see him going off on another adventure.
But who knows. The sky's the limit with this series and its premise. That's what's so exciting about it. Hopefully this game has legs and does good sales in the long run.
I also suspect there will be a Switch edition, based on Bethesda's recent support for the system (Skyrim, DOOM, Wolfenstein II) and Mikami's comments on the matter. Pretty much everything does gangbusters on the Switch. They could advertise it to the Nintendo core as "from the creator of RE4" (which is true, in a sense; he still produced).