Get the other Prima Luna, drive each channel by one and enjoy another or 2 of performance.
Maximize the potential of those speakers by getting them in the optimum position, along with attention to the room.
One of many ways to find the "perfect" spots for your speakers.
http://www.cardas.com/room_setup_calculators.php
Speaker location and room will do more than what you're thinking of doing.
As mentioned, your speakers are not setup for separate amps to drive lows/mids and arguably wired in a "better" configuration-single post.