No problem at all - but in many ways Evernote's text capabilities are just icing on a very big storage and searching cake. If there's not already an add-on for Evernote (see Trunk) that helps with Outline note-taking, there probably should be - but Evernote's concentration on improving their core process will likely mean any more advanced formatting of text notes is still somewhere over the horizon on their route plan. You'll have the audit trail of previous versions of the notes, and a shiny new copy of your latest draft as the current note. It's pretty hard IME to make a good outline directly from a source - you need some rough notes to be working on and the best way to use Evernote might be 1) for the rough notes stage, which then can 2) be extended by the more coherently formatted outline and 3) (if necessary) by a more fleshed-out 'final version'.

Of course you could use another form of dedicated local or cloud outliner (I'm boring, I use my MSWord) and then cut/paste the document into Evernote, or -if your outliner generates a supported file type- you could embed or attach a saved file. As you note, it's possible to do some limited layouts with bulleted or numbered lists - hit ~tab and ~shift+tab to demote / promote lines but if you're looking for headings and styles and other conveniences, you're out of luck.

Short answer: Evernote doesn't do outlining.

Cloud outliner mac