Marantz av7005 vs av8801 vs Theta Casablanca

So I recently started upgrading some of my system starting with the speakers. I used to have a full Polk lsim 7 series 7.2 system. I have replaced most the Polk speakers with Legacy Audio, Focus se for the front, Marquis center and the new foundation subwoofer. My current pre amp is the Marantz av7005 with Emotiva xpa-1 gen 2 monoblocks for the front 3 channels, marantz mm7055 for the rears and surround. With the new setup I have found a limitation with the av7005, pro version of Audyssey no longer available. The av7005 does not let me run the front 3 channels, along with surround and back, in full range. I recently came across a deal on both a Theta Casablanca and a av8801, decided to buy both and give them a try. I have several questions. Will the av8801 allow me to run full range with the all of the channels? I believe that the Theta is a gen 1, would it be worth bringing this thing up to a newer configuration? I am still in need of better surround speakers and rears, should I try to keep going on the full range thing, legacy line, or dose anyone have suggestions for these speakers that would match with what I have. And last question, should I add width and or height. Thanks guys.

I should add that I watch lots of movies but also listen two channel.