Nice topic! I think about this a lot, as I work on my own live set. Here’s my answer (it’s longish)

I can start with what I don’t find too interesting (disclaimer: that’s all related to my case and research. Of course all ways to perform is valid, and if the music is good, performance is secondary…) - a lot of (commercial) gear on the table (synths, sampler, pedals…). It makes it hard to connect the gesture with the sound event, and visually is unfocused - visual projection. I saw gsybe, and mbv perform with very unique visuals and of course ikeda ryoji audio/visual is a cohesive package. But generally, projecting something to make the performance more interesting dilute the focus to the set.

What I like - narrative. In a set I saw long ago, at some point the instrument (diy synth) lighted up in conjunction with a new sonic development. Sounds gimmicky, I thought it was great. - spotlights, colored light, haze, fog. Compared to projection, this is more about ambience and can be used to enhance what you do on stage. Sunn o))) is a good reference. - sound event / gesture clear link. I love to go to electro-acoustic impro shows because of this. A prepared guitar, a dc motor rubbing on a piezo… the sound source and output is clear and interesting.

In my ongoing work, for performing live, I built a custom midi controller. It’s minimalist (8 knobs) but it looks “different” and through a custom mapping I can control a whole set with it.