Storyline & Mobile Optimization

I'm about to embark on a new adventure I've never tried, so I'm here to get advice from our amazing community to try and avoid shoulda, coulda, woulda's.

I'm designing/developing a course for 20-somethings. The client wants the content to be optimized for mobile devices, but the level of customization requires that I author completely in Storyline. (Embedding into Rise360 just wasn't cutting it!)

If you've developed a course in Storyline with the intent that learners complete the course on their cell phone:

• What advice do you have in terms of technical set up (adjusting aspect ratio to 16:9, etc.)
• What interactions work well on a cell phone?
• What should I avoid?
• What questions aren't I asking right now that I should be? ;)

Thank you in advance for your insights. I'm including a VERY rough sample from our proof of concept testing for a flavor of the course style and a picture of a turkey since it's Thanksgiving for you American devs!

TYA- Sam