I actually love that separation. QML is a great language for writing beautiful, responsive, modern UI with animations easily. C++ is great for performance and logic. I don't like Javascript but I don't need to write a whole lot of it. I wrote my note-taking app's block editor in QML and C++ if some people are curious[1].
I gave Notes/Plume a try a year or so ago, it was an interesting experience. I ended up falling back to Joplin as I could use it on macOS, iOS, and Fedora with synchronization via Dropbox.
I've always been curious about productizing apps like these, from a financial/business perspective have you found Daino worthwhile or enough of a success (by your standards) to continue developing it as a proprietary application?
Did you ever write a pure C++ Qt application with QtWidgets?
Yeah, I appreciate the separation as well actually, even though I'm not a fan of the langauges involved (no issue with QML, dislike JS and C++). I've made a few things with Qt and despite my feelings on the languages, found it to be pretty useful and capable, and the learning curve wasn't that bad imo. I can't recall using much JS to be honest, but it's been a hot minute since I worked with that.
That said there's simplicity to Iced being pure rust managed through cargo that I enjoy. Though it should be said that my "learning curve" for Iced was much lower than it might be for others as I discovered it well after I'd adopted Elm (which inspired Iced) and - independently - Rust, so Iced was pretty easy for me to grok.
I don't think there's a right/wrong way there to be honest, both approaches have their pro's/con's, and my main issues with Iced vs Qt is largely a matter of maturity/prevalence than any specifics with the implementations/workflow themselves.