Speaker crossover settings are generally most closely tied to the speaker's range - how low a frequency the speakers can reproduce. With that in mind, I'm including the -3dB point for each channel.

All speakers set to "small"
mains: 60Hz (-3dB point: 30Hz)
center: 80Hz (-3dB point: 42Hz)
surrounds: 80Hz (-3dB point: 60Hz for side surrounds, 50Hz for rear surrounds)
six-channel analog bass management "on"

Your settings seem pretty reasonable for the speakers you're using. Have you tried going up one notch on some of your speakers (60Hz for the mains, 80Hz for center)? I've known several folks around here to suggest taking the -3dB point and moving up an octave (in other words, doubling that number) to get the crossover point, and while I haven't used that advise in every case I have found it to be useful for best integrating my mains and center to my subwoofer (an LFM-1).