Redactor sucks. There are numerous issues and bugs with it, the settings don't make sense and contradict each other, and pasting doesn't work correctly. A lot of times, it produces broken output – for example, it sometimes forgets to wrap the content in a paragraph when it's supposed to, and vice versa.
There isn't a huge list of alternatives:
- I haven't used CK Editor in a while, but last I checked, it was just as bug-ridden as Redactor.
- Vizy looks nice, though I haven't used it in a project yet. It's not free, though.
For now, I would use redactor, but limit its scope, so its bugs aren't too noticeable. Don't allow editors to include images or iframes in it or edit the source code directly. Instead, use Matrix fields or Neo fields to model rich content, and only use Redactor for basic formatting. This provides you with more control over the layout and HTML output, and reduces the frustration potential for your editors.