I will be upfront about this and I apologize if this seems like an attack on anyone. It is not. It is simply the way I feel about live performance and electronic live performance, in particular.
First off, I admit that I don't care very much for repetition or wild impromptu in music. I have been to shows where I didn't care much for the music, but thought that the performance and show were amazing. Vice versa, I have also been disappointed with a performance from an artist who has music I love....
(a side note: I like songs with some sort of structure, planning, melody, theme, motif, but above all; progression. I think that interesting music progresses during the song. This could simply be the transition from a verse to a chorus and back to a verse. It could be a tempo change or key change or nuance in sound. These changes don't have to be drastic; they can be subtle. Something that I try and do with my music/song is to never repeat something exactly more than 3 times. I feel that the brain gets bored (at least mine does) after 3 times of hearing it. This is a common psychological feeling - often the reason that there are drum fills and breaks every 4 bars in many songs.)
Electronic music has many challenges in live performance - especially now when the computer or modular synth becomes the crutch of musicianship. I have seen many, many, many shows where the artist is hiding behind equipment or a computer screen and it is not obvious what the artist is actually doing live? Are they even playing music? Maybe for the DJ/ dance culture, this is an acceptable format for a "live" show. I feel that for myself, though, it is not something that I would feel comfortable doing and I don't especially enjoy seeing shows that are like this. I view live performance to be literally performing something live.
Most shows that I play require some backing tracks to fill in the rhythms and sounds that are critical to identify a certain song. Some important challenges come along with this that may or may not be obvious. Which sounds are on the backing track and which sounds will be played live. What equipment do you bring to a show to play these live sounds? How much of the performance is props and gimmicks and how much is actually playing a musical instrument? Vocals aside, how does one put together a set that will capture the audience's attention - even when they are not your friends, but strangers that just happened to catch your set for the first time and have never heard of you before?
Live performance is a delicate balance between playing the music that you create and giving the audience something to watch and hear. Sometimes the artist sounds so amazing live that just hearing their voice or seeing them play their instrument is captivating. Sometimes it is more about the visual effects that the band/artist puts on the screen behind them (not that there is anything wrong with this approach, but unless the video/film/slides/photos/images were actually made FOR the band, I feel that this is sort of a cop-out - where the band is sort of taking credit for something that doesn't have anything to do with them [(for this same reason, I rarely play cover songs of other peoples songs)] ).
Live performance is not gimmicky - if you bring a prop or special instrument, it is best to not overuse it and be subtle about it. Use it so it works well with the song context or space between. Drawing extra attention to it or calling it a special name on stage is just silly. No matter what I bring to a show, I tend to follow a rule of not using anything more than two songs during a set.
Live performance should be transparent. This means that the artist should be doing SOMETHING that the audience can see. Preferably, this something should change the sound of what they are hearing rather than just being a visual stimulus. This also means that the artist should not be hiding behind equipment.
I should also point out that a live performance should not be endless noodling or soloing around on an instrument while making an expression with your face as if you were constipated.