In this article I discuss what I did to wire my new home, what it cost and what tpyes of things we needed to consider before we started. These were some of the itmes we planned and wired for; Phone Ethernet, Cable TV, Alarm Keypads, Distributed Music System, Plasma TVs and surround sound to name a few...
Personaly I would have put in a standard alarm system, have a TV and HiFi room, and us a wireless intercolm.
As for networking, I would consider a high quality wireless for a mobile laptop, and have a wired network for the main computers, probably in one or two rooms that are close to each other.
For the security cameras, I would have gone wireless.
My cost would be less than 1/2 of what you spent.
I wired my place for telephone, cable, and networking. I spent about $300 for everything. I did the work myself. The complete job took me an afternoon (about 5 hours).
As for having speakers around the house for music, I find this to not be practical. for the cost of just good quality speakers and the wiring alone for each room, I can have a discent Sony or Panasonic mini stereo in each room, that is independent. These give very good sound for the cost, and are very dependable. This way, each person can have their own programing in each room. I also have a TV in each room, that works from the cable system. I ran RGU 6 with the wall plates through the place, fed from a master high quality amplifier with an 8 way splitter on the output of it, that is puting out the signal to each room.
Personally, I'd run multiple CAT5 and forget about wiring specific to audio and phone. You can use CAT5 for phone, and with a little cleverness and equipment can also distribute audio quite effectively over it. I think most alarm systems can also use CAT5.
Some coax for video would also be on my list (although advances in the use of CAT5 may soon make that spurious, too), along with generous power outlets.