When will we get a proper form factor adaptive layout function?

Question

I'm deliberately not putting this in the long requested features thread because adaptive layout isn't a feature, it is a basic function of all Windows Apps, except for those built by Project Siena.
I was dumbstruck to see that the often requested "support for different form factors" was translated to "exclusively for a specific form factor". Designing for one excludes the others. This is not at all useful.
While I can understand the need to design for different screen formats portrait versus landscape, because of a fixed layout there should have been:
1. a template that works for 16:9, 16:10, 3:2 that would adapt to the form factor
2. maybe a portrait template
3. and most important a function that combines two templates (as per above) and writes out some code that detects orientation so that
4. Project Siena could produce/publish/publish for store a single project that would allow use on any form factor, any orientation without needing to specify landscape/landscape flipped only - or portrait (etc.)
What do others think? To me this is more important than more widgets or anything else. Including Windows Phone would be a nice extra, but to be able to product a single project that would work transparently on all form factors and orientations is now the
single more important function I need.
It would be good to have a response from the community and a statement from Microsoft.
As someone who has 14 (not a typo, 14) apps built with Project Siena in the Windows Store, this is important.
-- Barb Bowman

Answer 1

This is a reason why I still don't work on my project design. I don't want to end up to recreating all my design. I think the only way is to add percentage size and positioning into visuals so they will adjust by it self when run
on different devices. I don't know how it could be done without it. Once you create app with visuals width set to 1000 pixels and run it on device with resolution 800*600 (example) then it obviously won't fit. However to set the visuals
width to 100% would fit logically to all devices. But this option should be implemented log time ago so we can prepare our apps for this new feature. Am I right or you working on different solution?