Paul,
18 and 20 are definitely in the right track. 18 probably even better.
The 2 aspects we need to convey are intelligence and graphs, which 20 starts to do, but isn't obvious. It also looks busy.
Question for you and other designers: Why am i not seeing indepth/sharp images like the ones in this link for example. Ignore the actual content, just look at the rich graphical quality. Again DO NOT replicate the actual images.
http://www.iconspedia.com/icon/bar-graph-4283.htmlhttp://www.iconspedia.com/icon/address-book-8135.htmlThat's the richness that I am looking for. Hope this all helps. Any questions don't hesitate.