Yeah, the acoustic guitar is an amazing instrument. Beethoven loved the guitar, and called it a portable orchestra.
I have a degree in Music History, so like you, I like to do my own arrangements. Sure, the first draft is basically just the chords with the tune on top, but I always try to add little ornaments, deedly-dees, walking bass lines up and down, cool little turnarounds, imaginative intros and endings, etc., I usually try to arrange at least one passage that is beyond my ability, and then torture myself for a few months to master it. That's how I know I've improved. I look over all my arrangements, and all the hard passages that I wrote, and then conquered, and I have actual proof of my improvement. That's satisfying, right there.
You can pick up used trumpets on Facebook Marketplace for cheap. The most common mutes are straight and cup mutes.
Jazz players use them a lot. It gives them a cool, quiet, strained sound. Miles Davis used a straight mute often. So did Dizzy.
Get a cheap trumpet, stick a mute in it, and stand in your closet door, and play into your clothes.