Adding support for style tag in Alloy XML views would allow you to add TSS styling to a view without having to create a separate TSS file.
This should also support a "src" attribute which could then reference another external file which would allow a TSS file to be shared amongst multiple views.
This would solve some of the problem that exists by the absence of a widget-wide tss in Alloy. https://jira.appcelerator.org/browse/ALOY-1729
It would also solve some of the problem that exists when trying to override widget styles in your Alloy app. Currently, you have to create a theme style in order to be able to override a widget style.
I have implemented and released this a feature for Turbo and I can create a PR for this if you support this feature and want to have it in Alloy. https://github.com/brentonhouse/titanium-turbo/pull/206