FluentAvalonia VS lambda-converters

This is what you need : https://github.com/amwx/FluentAvalonia

FluentAvalonia

If you want to have the FluentUI theme you can use https://github.com/amwx/FluentAvalonia. I used this for another project and didnt have any issues.

It's literally not the most basic control for Windows development. That would be something like Window, Button, or TextBlock. If you're only using the basic features of a NavigationView, then you can implement it using a simple ListBox with some minor styling instead. The fully featured NavigationView from UWP has a lot of complexity that most devs won't need. You could also use the implementation from FluentAvalonia

There are many cool custom themes for Avalonia, also default Fluent theme is already very good looking. Try for example this https://github.com/amwx/FluentAvalonia

But, going by the Avalonia route, you have the promising FluentAvalonia project for the Windows 11 look & feel. I was a bit overwhelmed by Avalonia when I tried it but especially for cross-platform projects it's of course a solid contender and probably a strong alternative to MAUI.

Yeah, I think some things go a bit too far. I also think they tried too hard to solve certain things (poorly) in XAML that frankly shouldn't be declarative. There's a few things you can do to make WPF less painful. I recommend using https://github.com/michael-damatov/lambda-converters, for example, rather than writing whole-blown converter classes of your own.

something like https://github.com/michael-damatov/lambda-converters should be built in because writing a whole-ass class is inexplicably verbose for 95% of things people do with converters

instead of full-blown converters in C#, let me write inline lambdas right in the XAML. Blazor lets me do that, sort of. (I use https://github.com/michael-damatov/lambda-converters so I at least don't have to write entire types.)

I haven’t dived too deep into MVU either, but at a glance, it seems more focused on lambdas. IMHO, one of the weak spots in MVVM/XAML is how much boilerplate you have to write for a converter, when oftentimes just a lambda would do. This lib helps, but it still isn’t inline with the rest of the UI.