I have the CS20 center, Bic F12 sub, and recently upgraded my fronts to Monitor II 60s. Sounds GREAT. Monitor II 30s would be perfect for surrounds (very similar to the Polk R150s I'm using for same).
I set all my speakers to small, and crossover at 80hz on my receiver. On the sub, set phase to "0", crossover knob on sub to max (180hz I think), and the switch to the digital 5.1,6.1,7.1 setting.
I didn't like what Audessey came up with for channel levels, so I did all my own settings for the speakers--YMMV. I started with them all at "0", then found I like the center at +3 or 4, sub at +3 (then adjust sub volume on sub), and surounds at +2. Since your Denon has the advanced Audessey stuff, you might try that, then tweak from what it comes up with (beware though, Audessey often makes the front mains "large", which I would advise against).
Have fun with your new stuff!