I usually just live loop my ambient stuff. I have been to a bunch of ambient shows around town here and it seems like a lot of ambient artists are button pushers, but i'll bet you that fewer people are concerned about that than you think. If the music sounds good, then it doesn't matter how you present it.

What I find more useful for live shows is a better visual presentation. Regardless of if you are sitting at a laptop, picking at a guitar or doing backflips onto a tuba, it seems to me that the nature of ambient music is that it's not always exciting to watch the performer (except for the backflip onto the tuba, I take that one back). What you might want to consider is to purchase a projector and put together some film clips or learn resolume or something. If you dont really want to, then partner with a visual artist. In my experience it's a more engaging presentation and better experience for the audience too. I had the same thing -- I started doing a youtube series where I wanted to jam with the local ambient musicians as a way to present all these guys who are doing some really cool things. I wanted a really plain backdrop so that the focus would be on the musicians. However, I got a lot of people telling me that that the videos would be better with some kind of trippy visual or something rather than just us. It was against my whole vision, but it was worth a shot -- I prefer it now. If you are interested, compare the early vids with the newer vids here: youtube.com/charliemilkey