i suggest you create a project template for XAML/Typescript and not just HTML/Typescript
I suggest the following three items:
B. You should create RIA services for XAML/Typescript just as you had in Silverlight/c#/vb. And you will be forgiven for leading developers to Silverlight and killing it.
XAML/typescript, HTML/Typescript, HTML/C#/VB etc at no additional cost. I expect Roslyn at least to achieve this last point. but the first two points should be achieved immediately.