🚀 go-pugleaf

Frame is about books; that is, tables of contents, lists of figures, lists of etc., 
Indexes, cross references, templates that provide a common look and feel across a series of publications. The majority of Frame users create content in a template designed by a graphics designer. 

InDesign is about flexibility, creativity, and can be best exploited by a graphics layout specialist who has content provided by others. 

The InDesign interface may look easier than Frame but that's only because it's heavily influenced by Illustrator and Photoshop, whereas Frame is not an original Adobe product - it's interface existed before Adobe bought it. 

Don't be concerned about size. Size doesn't matter it's how you use it that counts. 
Cheers 
Ian