Hi Andrew, thanks for the suggestion!
Personally I think this is more plugin territory than theme.
For example, if you had a complicated set up where some widgets showed up on some pages and not others and you switched themes, you would expect those changes to stay with your site, not be lost with the theme.
There’s also the fact that the more plugins I release, the more updates I have to do. If something already exists (and is coded well) that is updated by someone else, I’ll usually just point people to their plugin.
This is why I haven’t done any slider plugins as well.
Of course, if some day there isn’t a good option out there, then I’m all for creating one 🙂