So my go-tos are bodysuits, crop tops, I like to wear a cute little crop top, but then maybe a jazzy pant. I wear a lot of pants.
When it comes down to the music, it's just you and the microphone. It's not you and the record execs.
There may be some backward countries where the mass of the people are on a subsistence level and where, as an aftermath of wars or partial crop failures, the standard of living has to be drastically reduced, but this certainly is not the case in our prosperous nations.
If you have multiple events and don't want to spend a lot, I think a solid colour crop top can be used for many different looks.