I would look at Mainstage first, as it is not a sequencer but more a sound template setup way to go for live performance.

https://support.apple.com/kb/ph13512?locale=en_AU
Remeber it islimited in shaping your sounds and the layout is visual and you can see a keyboard on the screen. The cost of the software indicates the limits too.

Great for cover band music and if you are not changing things all the time. Mainstage doesn't have all the knobs and sliders to be mapped. It allows 2?! And that main slider you can make, say for volume of an instument, stays there for that instument. When you change the instrument you must also map it again for the next instrument you want to use.

Ableton Live is a full DAW and the basic version has 1500 plus sounds and you run it differently and you can have have all the knobs and sliders for you tweaking etc. Once you have it all setup it will stay there and is more professional too.

You pay for what you get.

There are two main views in Ableton. You can also insert voice tracks or midi ( multiple) etc etc...... or not.

Allan