We created an online course through FutureLearn a couple of years ago, for quantum computing:
FL forced me to rethink how to learn online. It was a great experience. It was also a *tremendous* amount of work -- we spent *hundreds* of hours preparing the materials, shooting and editing the videos, doing the very limited amount of animations we did, prepping quizzes (creating effective multiple-choice quizzes is hard, and I don't think we've mastered it yet), developing JavaScript apps, making sure materials are accessible to the vision and hearing impaired, etc. It was more work than creating a classroom course, easily as much as writing a textbook, except that it involved a *team*, not just a solitary professor.
Obviously, this doesn't scale, in terms of faculty time, latency and university out-of-pocket costs.
We (Keio SFC) also have our "Global Campus" website, an archive of thousands (tens of thousands?) of hours of lectures, mostly in Japanese. Many of those are just videos of in-class lectures, many shared live at the time of recording with other campuses/universities (which was usually the incentive for recording them). They are a tremendous resource, but post-facto serve as the equivalent of a library of videotapes, rather than a true online learning experience that takes advantage of everything the Internet can be.
So, we need something in between: something that will allow us to quickly achieve a moderate but effective form of online learning: that engages students and keeps them engaged; that provides some form of interactivity and feedback to the students; that scales to working for hundreds of courses shifting online with a week's notice. What does that look like?
I've spent two years thinking about it, and I don't have an answer yet...
(Also, keep in mind as you move your courses online, that not all students have access to high-quality, high-bandwidth, unlimited-volume Internet.)
