IB is a mess:
- No way to define reusable styles.
- No way to compose layouts out of other layouts.
- Trait classes are way too coarse to be useful.
- Versioning of Storyboards is a nightmare.
- Anything beyond trivial auto layout editing is useless.
- Segues force you into stringly-typed APIs.
- @IBDesignable is still super buggy.
I've been much much happier since I dumped it and started doing everything with SnapKit.