Tim - I guess if I was running the small multi-op, I would book MYSELF first, THEN book my guys second. I would personally push for more than 30 weddings per year, and leave the parties and easier (lower paying) events for "the guys..."
As far the Bose goes, yes, it carries SOME weight with those who put importance on names they know. I've said it over and over again, say what you will about Bose products for pro sound, the public at large sees them as a quality name. Their marketing team is unparalleled. I've never seen the Bose as an upsell. For me it's always been a reason to charge more on EVERY show.
As for the DJ Power system, my guess would be that the public opinion on that is "ho-hum... another computer DJ..." The general public has no basis to say that this is better than the guy with the Wal-Mart Dell laptop that he paid $500.00 for
So to take a long way to a short answer, in YOUR shoes, knowing that I am counting on filling that date in order to make my bills, I might have tried to see what I could do to get closer to her number. Maybe drop any lighting, or even discuss doing a shorter event (5 hours) with a discount on the OT IF the party is completely off-the-hook, and everyone wants the show to go on...
You'll notice I'm not saying I would have given in, but I would have tried to find something "value-added" to help her justify my price, or found a way to do a bit less work to help ME justify lowering my price...
As a sales technique, you can also ask the prospect "If price were equal, would you hire me or the other guy?" If the answer is you, the next question is "Why? What makes you want my services over the other guy for the same price?" Let them tell YOU why you are better. Then ask if those reasons (and their peace of mind) are worth the difference in the money. Get them to tell YOU why you are better!
Of course, I could be COMPLETELY wrong... (It's kinda late, and I've taken sinus meds taht are kinda messing with my head... Your mileage may in fact, vary!