I have been using Entity View Modes to organize my fields, have different display types, and use Field Groups to add bootstrap-style wrappers around my content.
As often as humanly possible, I have views and panels render nodes with these view modes to keep a consistent look throughout the site.
I keep hearing about Drupal Field Collections, and have a basic understanding that it goes further and makes an Entity out of the grouped fields. Seems like a different approach to achieve similar results. It has a lot more uses, but also a lot more open issues, and needs other modules to integrate with Views and Features.
I'd love to hear some thoughts on this.