Couple SEO questions

Alright so I have finally started a long term project that has made it off the drawing board that I will stick with and I have a few questions on SEO, as it is not my strongest point yet. I just want to make sure that I am doing everything right to not receive the google banhammer and get the best search results. Here is what I am doing: I have one main site dealing with a certain niche, but this main site is not very specific and contains info on all of the many many parts of this niche. I have a large amount of smaller sites dealing with very specific parts of this niche and these sites have links back to the main site. The mini sites are bookmarked to hell and each have about 3 web 2.0's with links back to them.
All this being said, am I doing everything right, is there anything I can do better, is there anything else I can do, and am I doing anything that will cause a google ban? Thanks in advance.
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