Looking to upgrade from Boston Acoustic Micro 90x 5.1

Im currently using a Marantz sr7005 coupled with a Adcom GFA 550 to drive my multi room. My main listening area is 17 x 20. Im looking to stay small with no towers. I feel my current Boston Acoustic is a little underwhelming. Especially my sub, which i can never seem get get quite right. Systems I'm considering are Gallo A'viva, Definitve Tech pro cinema 1000, Cambridge minx s325 and the Orb peoples choice. Im not opposed to building a system ,i really lie some of the HSU subs. I usually do about 65% watching TV/Movies and 35% for music. Any advice of which of these or any other system would be a substantial upgrade from my current set up would be greatly appreciated. Larry

Thanks. I can go a tad larger, but I want to stay bookshelf for fronts and surround. I limited with size for my center. My current is 6.5 x 12, which fits perfectly in my builtins. However with a little retrofitting I can go up to 6 x 24.

Are there any other obvious choice i'm leaving out? I was also thinking building a ascend acoustic system. Not sure if the Sierra 1 is meant to be placed in a shelving unit?
Edited by gelly - 2/11/13 at 7:05am

Thanks, With regards to the HSU or SVS subs, which model/size do you recommend? also is it essential the sub be facing you? I currently have my sub behind,in a corner of my listening area. Which surrounds make the most sense? or does it depend on what center and sides i go with ?