Hey I never shared this with the group...and I don't know how applicable this is now. But 2 years ago, I started a project to bring some of the primitives that we were accustomed to in WPF to Xamarin Forms. I made a prototype over here
that shows a primitive ellipse shape that only respects hit testing in within it's actual visible area (Xamarin by default returns a positive hit anywhere within the element's rectangle).
I stepped away from Xamarin but I did ping the team to show them what I was doing I'm not sure if it was picked up but one of the team members did take a liking to the concept and started writing code using a 2D vector library to implement the primitives.
One thing I also demonstrate in the prototype is the concept of Brushes (I implemented the solid color brush from WPF but GradientBrush would be possible as well) again Xamarin Forms didn't have this primitive at the time I'm not sure what the state of affairs is two years later.
I also wanted to implement StoryBoards for Animation because currently animations have to be triggered in code behind.
Anyway, I thought I'd share in case anyone else is interested in chipping in and getting this published for the XF community.