Will, I forgot to mention one thing that you may want to try. You can vary the tempo of the tremolo in some places, particularly on whole notes or longer, or at the end of a phrase, perhaps slowing it down a bit, for emphasis.
I see that violinists sometimes do the same thing with vibrato, not always maintaining the same tempo on the same note. You can see their fretting finger rocking back and forth a little slower on part of the note.
That's the great thing about music --- there's a;ways something else to do or try! SETH
Okey-dokey, Will, I was able to create and have attached an MP3 for you! It's "The World is Waiting for the Sunrise," a well-known plectrum banjo favorite. I've included tremolos with varying tempos, as I noted in other posts in this thread. Hope it demonstrates what I was explaining, and that it's helpful. I would not normally play this tune with quite this long of a tremolo-only section --- too much tremolo is just as bad as not enough tremolo, in my opinion.
There is a much more skillful version of this same tune on YouTube, done by my teacher Don Van Palta, the "Flying Dutchman," with a few key changes and some wonderful strums and fancy fret work. Here's the link: youtube.com/watch?v=2bhzFMtbtr8
It took a few tries to get the MP3 into my computer and then onto the Banjo Hangout. But as I tell folks when our PA has a problem during a show, "I'm a musician, not an electrician!" SETH