Wish No. 1
A Windows version of Ulysses or its functional equivalent. It would need to be fully cross-platform and have no subscription.
There is actually a suspiciously Ulysses-like program on the Microsoft Store called Inspire Writer from a publisher I’ve never heard of. I mean, it basically has everything I like about Ulysses–again, suspiciously so. Whether they were just “inspired” by the app, reverse-engineered it or just plain decided to copy its features and UI, it makes me feel a little skeevy even considering it. And it makes me lament that there are no other writing apps for Windows that are like Ulysses. iA Writer is a pretty good markdown editor, but it doesn’t work well for long form (novel) writing, and most other markdown editors are the same–excellent for writing blog posts and short pieces, but not much else.
Odds of this happening: Pretty much zero. The company behind the app is one of those weirdly proud Mac-only (except now also iOS and iPadOS-only) developers. Also a Windows version would totally have a subscription, anyway.
Wish No. 2
Scrivener fully supporting cloud saves and syncing.
Scrivener was never designed to work with cloud services like Dropbox or OneDrive, due to the way it saves (by default every two seconds!) and the way it handles files (each project is not just a simple document, but rather a collection of files that effectively appear as one to the user). They cobbled in Dropbox support when the iOS version was released, but the official word from their support is to stick to using Scrivener locally and use cloud storage only to keep backups of your work.
It’s good advice, because it’s pretty easy to mangle your Scrivener files if you keep one document open (in error) on Computer A then go to open it on Computer B. Trust me, I know!
Odds of this happening: Very close to zero. I think we’d have to see a complete rewrite of the application, or a different “cloud-only” version of it, and neither seems remotely likely at this time.