Yes Sir - the multiple outs allow you to control whatever instrument you assign them independently on your mixing board.. the beauty of that is, without that option, ALL your drums would be on one or two channels and you'd have to adjust volume of each individual drum solely from the drum machine controls, which would be difficult because if you had the drum machine onstage, you couldn't be out front to hear it and mix it accordingly.. So, the more outs the better for live performance - actually, for recording too..
Ok, from the specs you listed:
TRIGGER OUT jack: I'm not 100% sure without seeing it, but usually a trigger jack is for a foot switch to turn the drum machine off and on.. so you could start/stop it with a foot switch
PHONES jack: For headphones
OUTPUT jack: Are there two jacks? If so, that would be your line outs - left and right stereo.. so you'd hafta mix everything within the drum machine..
MIX IN jack: Not sure, but I think you can plug an instrument into the drum machine here..?
MIDI (IN, OUT) That's to run it all through midi.. I've done it once to incorporate keyboards I recorded.. so, you could record keys, trigger them with the drum machine through midi so you'd have 2 or however many instruments playing that you need - all through midi tho, which can sound, imo, robotic at times..
USB port: Not sure as mine doesn't have one.. probably to record out and send signal to computer or other mixing device..?
Man, you're making me want to bust mine out and start programming.. I've been working on a new song the last week or so and need to put some drums to it to get a real feel for it.. That's what I use my drum machine for - to get the basic drum tracks down so if I bring in a drummer, they'll know how the song goes and then be able to add their own flavor to it..
Holler if you need to!
Friendship is like peeing your pants.. Everybody can see it, but only you can feel the warmth..