Yes, I recently transitioned to net core. First of I'd say that trying to find a 1:1 feature/convention parity between the frameworks won't work. E.g. in aspnetcore you'll add an attribute to model and after generating a new migration the column change will already be in-place. Most of the time it works out-of-the-box, you can always edit the migration if needed
What I found lacking (at the time) was specifically a better Webpack integration, similar to rails.
Also I got used to having rspec, in net core world you have xUnit which is something like ruby TestUnit.
At the start I also found DependencyInjection a bit confusing and also the fact that in Aspnetcore the models/entities aren't like AR models where you have a bunch of validation/instance methods inside it. In .net you try to separate everything in repositories/validators/viewModels.
But yes, unlike Rails, .net won't have an opinionated way on how to do things.
All-in-all I'm quite satisfied with the experience. Though I will say that Rails is still a tad more "batteries included" type of thing.
You don't have to support users who use your library internals. Django for instance didn't support everyone who relied on undocumented internals in its orm. The standardization for the latest release made those internals clean and documented, but unapologetically broke other people's code including mine.
