I'm upgrading :-)

OK, so I'm about to buy a Denon 3803 and I am going to put 5 new speakers on it.

Here's the room specs ..... 19x19 and the main entrance is an open wall about 12 feet wide, you come in from the foyer and this space is open. On the opposite side it's all glass with french doors out onto the deck. Ajacent to on the left is another opening about 6-8 feet going into the kitchen. In the corner closest to the main entrance there's a closet (more on this later).
The room has a cathedral ceiling to a height of about 18 feet.

I am considering putting in these speakers:

5 Boston's
The front main must be bookshelf due to the fireplace (the plasma will go above the fp). So I'm considering the VR-M50's for these (list at $700/pair)

The center will be the VR-MC (list at $600)

The surrounds will be the VR-MX (list at $800/pair).. the reason for these is because of the dipole .... remember the closet ? well one chair has to sit a little further into the space becuase of it, and as such I can't get both of the speakers located on the back wall, so I was thinking that this type of speaker would provide better dispersion of the sourround sound in the back of the room.

I currently have a Kenwood 150 watt sub ... have had suggestion to consider upgrading this. I need your opinions here too pls, thx. What might I consider putting in here, how big ? what brand ? why ?

So, what are some of the opinion's out there regarding this configuration.

Are there better choices to be made for the same amount of money ?

Any thoughts on the rear speaker placement ?

Thanks,
Mikey