Hi Crow, good choice of soft! You ask for experience with Renoise for live performances? Well, I’ve played with Renoise on a number of occasions, and it definitely has its benefits and downsides.
Compared to Ableton, Renoise is much more snappy in terms of switching channels, patterns etc. You can really f*** things up in a good way! Biggest thing you can for yourself is to learn as many of the keyboard shortcuts by heart as possible (especially the “global” ones). Go to the preferences > keys and hit the “print” button. Read the paper every night before going to sleep for a month, and you’re good to go 
Downside is, you’ll find it hard to “add” anything new to an existing track, while performing (I’m not speaking about effects or plugins here, more in a tonal/note-wise context). For this reason, my feature suggestions are, for the most part, directed towards the live performance aspect, because I feel it’s almost there. So here’s a little lowdown on the ones I’m personally most interested in (it will also give you a pretty good idea about the present limits to live Renoise usage according to /me):
#1: Toggle Follow In Sequence Editor
#2: Keyboard Shortcuts Mapped To Midi
#3: Crossfading Send Device
#4: Target Instruments With Midi
Oh, and then there’s the general points always worth noting about live performance / improvisation:
1: anything is possible.
2: any electronic musician will have to be extremely well-prepared, to be able to improvise.
3: (but that’s my personal opinion): people don’t care if it’s live or not if the guy looks funny, jumps up and down and waves to the crowd. Well, I dont do any of those things.
Track on 