You can type directly into layouts in InDesign and see your line and page breaks in realtime. I think where the problem lies in InDesign is that it is, at its core, a typesetting and layout application and not a word processing application. There is a lot of work to do to get to the point of being able to write in your layout, and pages don't get added dynamically when adding new content as easily as they do in a typesetting application.