When making setlists, I imagine each set as a one act play where each song is a character or an event. In this context, a song has a role and a personality. The opening song is vivacious and engaging. The next song or two develop the plot. The third or fourth song guides the listener further into the story. I use contrast, dynamics, tension, and release to build my set, hopefully leading to a dramatic finale. I can't say it always works, but when it does, it's great fun.
Planning setlists will improve your repertoire. Are there songs that always work? Are there songs that never work? Are there too many ballads and not enough rockers? As you build sets, you will identify the duds and replace them with better songs. With a good mix of rhythms, tempos, and key signatures you can create interesting sets that build to a big finish.
I label songs by title, key, tempo, year, and artist. This allows me to group them in interesting ways. You can also label them as uptempo, midtempo, ballads, or rockers. You can make a note of who sings or plays a featured solo. All this detail can be overwhelming, but if you get stuck, just remember it's only a setlist. Eventually, the audience will dictate what you play. Requests come in, a listening crowd starts dancing, things happen. You'll almost always adjust your set on the fly.
In the end, you don't need to get too precious about your setlists. The act of making one compels you to think about the important elements of your show; engagement, variety, pacing, and payoff. It's one more tool in your kit to do what music does best, to wake people up, open their hearts, and make them feel good.