I will start with the surrounds. You usually do not get any significant bass information for your surround channels and, if you do, it would be nearly imperceptible to your ears. Let your sub handle that. I have my 4 surrounds crossed over at 100Hz.

Your fronts depend somewhat on your listening habits and your preference. From a very quick read on the internet, it sounds like your main speakers are more than capable of handling the typical range of frequencies that you will get out of music sources. This is just my opinion, but I would try setting your mains to small and the crossover at either 40 or 60.

So, to summarize, my opinion is to definitely set your surrounds to small at one of the higher crossover points, and try your mains at small with a low crossover point and see how you like them.