The melodies I've been writing have been good in terms of notes and chord progressions, but they lack interesting rhythms. Some examples of good rhythms that are interesting are DROELOE's Kintsugi and Snow Shovels. Is there a catalog or a database containing midi/other formats with rhythms that can be applied to either melodies or drums? It should be similar to this but more extensive.
If you look for the term "rhythm vocabulary" you will find many books and other resources for developing rhythm. Many of the materials will be large compilations of different rhythm patterns intended to be learned by students to develop their rhythm reading, which you could use as examples or ideas.