I would love to use Qt for personal for profit projects, but at $79/month (the cheapest commercial option) I find it too expensive, as a independent developer with pet projects that might not generate much (if at all).

What other good options do you know for building multi-platform nice-looking desktop UIs, I dont want to go with electron but so far is the best option I see for fast and cheap development, with the tradeoff of 50mb simple apps and not so great performance.

"Dear ImGui" (https://github.com/ocornut/imgui) is an absolute delight to use. Can't recommend it highly enough. It's not suitable for every project, but when it does fit then I can't think of anything else I'd rather use.