Melodic Piano/Strings/Voice (need advice for later movements)

I love the minimalistic style and sound of Phillip Glass and Paul Cardall. I like to write around the tonic, keeping to one key, and using entirely consonant chords and harmonies.

I've no music schooling or lessons, so if anyone has advice on the following topics I'd love to hear it :)

Leading into a "chorus" (tempo feel, beat accentuation, chord selection)
Reducing elements to go back into a "verse" without sounding droll (melody modification, slightly new chords?)
How to lengthen a selection without sounding monotonous (when to add and remove elements to elaborate a part)
Given one inspirational progression, how to structure the rest of the song around it without other parts sounding odd

I know all of these are subjective, but I need opinions on what you all are doing!
I enjoy listening to your ideas on the forum! Perhaps I can find a collaborator on here? :D
-Matthew Petersen

Here are two of my works in progress!