Kabuki, Live's controlls are high resolution, most midi controllers are not. The ones are, are more expensive and most are like a recording console.
You can split the A/B, you need to send your tracks to seperate ch's in your audio interface. This option will open in the track's out menu only if you do have a multi out card.
scottanthony;
About how to work with a DJ mixer, you send tracks as a line out to the mixer, use live's faders as basic gain, just leave at 0db. you can also monitor from the mixer, and not "spend" ch from your interface.
You are not controlling live, you mix the audio after it comes out of live.
The way I have it now (I change sometimes) track 1,2 to buss1(track3)and out to the interface 1/2 outs

DJ mixer ch1. Tracks 5,6 to buss 2, out 3/4

DJ mixer ch2. all eff tracks, send returns, to out 7/8

DJ mixer ch3. Live's master to outs 7/8. I use it if I need more clips together w/ seperate control. for these I might use midi mix. I also monitor the browser from there. Hopes this helps.
Once you do that, you will feel the difference from mixing tracks to the master, or in the DJ mixer. You do need a good mixer to enjoy the benefit.