Fontana's staying for a 5-issue arc. Who, after her, could pick up what Rucka is likely to leave us with and do something interesting with it?
I'd be curious for Marguerite Bennett. She was going to be the writer (and I think had written an issue?) before Rucka stepped back in, and nary a whisper has ever come about what her plans were. I think her writing is fun and shows talent. I don't love everything she's done - I've stopped picking up Bombshells because it makes me yawn - but she seems to be an energetic creative machine.
I've always wanted to see Kurt Busiek really get a chance at WW. He wrote that mini-series drawn by Trina Robbins, but that was a story with a very specific, look-to-the-past and have fun with it purpose. He's written the random issue or two of the main title, but those were one-offs, I believe. Though people assume Winged Victory is his analogue to WW, he's said in interview before that he thinks of Cleopatra, if any, as being the Astro City "version" of WW, and I don't think he's ever written an Astro City arc focused on Cleopatra. He's a talented, solid writer, and he has at times been interested in WW. I'd be interested in seeing what he'd do.
Both Geoff Johns and Scott Snyder have publicly expressed interest in writing WW, but they're both incredibly busy with their own projects, and I'd really like a talented writer in it for a longer time, not one or two arcs.
Though I'm not caught up with it, I've really enjoyed Marjorie Liu's Monstress (I admit that part of the enjoyment is in how beautiful the art is), and while I never read it, she got much critical acclaim for all of her X-stuff. Maybe Liu?
As for artists, I'd like Bilquis Evely to stay. I'm hoping that the reason Mirka Andolfo is only around for two issues is that Evely is returning. I like her art, and I think it improves with each issue.
I think I'd wet myself if Jamie McKelvie or Stuart Immomen became the WW artists.