I've bought a projector since last year june.
The first one was a Toshiba TLP-T100 which is actually not the right one for home cinema. So last year december I bought a Epson TW700. I've had it calibrated for getting the most (colors and greyscale etc) out of it.
I use the projector as an alternative to watch movies. For daily use I have an Avant RF DVD with penta's and 6000's.
I also bought an electric screen from proluxx which comes down just in front of the avant. So you can use the same speakers and the center from the avant will still be used.
In your setup I would, if money isn't a problem, buy a JVC HD1. Which is one of the best projectors at the moment. Some fanatics say it is even bettter then a Barco or Ruby (CRT projector's).
Then I would use a litronic convertor to convert the projectorsignals from the BV7 to the projector (every model with a Com port is usefull), to control the projector.
The screen can also be lowered by use of infrared signals from the lintronic box.
The only problem is to get a proper videosignal from DVD, HD DVD or Blue Ray. I bought a Denon 2930 with HDMI specially for the Epson.
I had the experience that the quality of the Denon is far more better then the DVD player from the Avant or DVD1.
It has besides the very good picture also HDMI, component and a good scaler (720P, 1080i and 1080P) inside.
Off course you can buy a BS3 and use it with the speakers you already have. Both the LCD/Plasma and projector can be connected through HDMI. But that isn't the cheapest way.
A DVD/HD DVD or BR player can then be connected with HDMI to the BS3.
I think that It will probably the easiest way to use.