Love that you want to work on projects that actually release. I founded ComposerScout, a free spot where game devs go to find composers. You can tag yourself as open to rev share or hobby projects so the small serious ones find you first, and keeping the music in your portfolio is up to you. It's free to join, and I don't take a cut of your gigs. We'd love to feature you there: https://composerscout.com/#edit