I think you're on to something with the shorter songs. I read an article on The Outline called The Rise of the Very Short Song a while ago about how popular songs are barely scraping two minutes these days.

Things have come full circle - the earliest recorded music on cylinders was less than three minutes because that's all the format could support, and now many people's attention spans can't support three minute songs.

I'm also on board with writing shorter instrumental pieces, as I'm planning to do short interludes based off of guitar arpeggio loops in non-standard time signatures, then adding many layers of various instrumentation over top. Should be fun!

Good luck to you in your creativity as well!