Option 3 seems like the most ideal.

I use dropdav.com to connect iwork to my dropbox using webdav. All that is needed is the ability to connect to a webdav server. It might not be the most elegant solution for file management however. But seems simple enough to implement.

First of all, great app. I'm learning a few new languages and it's nice to be able to jot down code on my ipad as i go along. However if my syntax could be checked from within the app that would be awesome. Currently i copy and paste into a online compiler. For scripting languages like python it would make such a big difference, and hopefully shouldn't be too hard to implement.