misc
Its too bad you already have the 170s (for surrounds). They're overkill IMO for that duty and the HTM-200s would have weighed less. Even for DVD-A's/SACDs, the HTM-200s do a fine job.
IMO, the perfect Ascend setup with takes into account a visually maximized setup is 340s across the front, and up to 4 HTM-200s in the back with a nice sub.
Azanon
Sierra-1 - Mains+Center
Surrounds - HTM200SEs (x4 in back, and x2 Atmos)
Sub - SVS PB-2000
Receiver - Onkyo TX-RZ1100
Oppo Darbee Edition Blue Ray
Sony 4K blu ray player