I have been working on this for a few months now off and on. This is how I envision views slideshow working.
Views slideshow is a really generic api consisting of 2 parts.
ex. every time a slide changes the slideshow will fire a change event that will be sent to the pager and the pager will handle what happens to it when a slide changes. In a normal pager this may mean the correct pager will get an active class. In a carousel pager this may mean it moves to the associated pager and gets an active class. But the key is that the pager handles this action.
The idea is that we will be able to combine different pagers with a different slideshow, or different pagers with different controls with a different slideshow.
I will soon attach a patch that has the beginnings of it. It still will need some serious work. There isn't a great deal of commenting so It may be hard to follow, but I wanted to get my ideas out so people 1) understand that I'm still working on this and 2) can provide some input or patches on how to make this better.