This PDF in reader's spreads is what I would use for my textbook teaching my six-credit Digital Publishing community college course for the Business Graphics degree I designed, taught, and led for 18 years. This is a major update for me. Many of the changes I've been waiting for with ePUB production have been implemented. InDesign now stands at the top of the heap for book production in general and ePUB production in particular. You do not need to know code, though understanding how HTML and CSS works will aid your conceptual understanding.
The new fixed layout ePUBs would show gradient paragraph rules, gradient strokes and fills in tables, and much more--but justification does not work in FXL. The exported ePUBs upload flawlessly to the iBooks Store and Kobo Writing Life.
Finally, the 21st century book publishing software we need is within our grasp. There's still more to come, but the present version is very good.