I agree with much of what you posted here. I'm not sure rituals would be a good idea, but a rationalist's version of Christmas would be nice. And of course, meeting in person, perhaps even hosting talks by various speakers from the local area and beyond might be of use too. That would require a more coherent definition of secular humanism than seems to be in vogue with the masses at large at present, though.
I imagine something similar to the Singularitarian movement envisioned by Ray Kurzweil.
Interesting article, and one of the few I've seen that has bothered with this idea. One of the big problems (as noted elsewhere) is that there is precious little that holds secular humanists together in a coherent, close knit society like religion does. In fact, that's probably why the vast majority of the planet's population professes faith in God/holy book/enlightened savior. I have never considered it likely that the average Catholic, for instance, really believes in the doctrone of transubstantiation. What is so obviously not a miracle (bread remains bread, wine remains wine) is transformed into such through the miracle of community.
As a recent study points out, it's community and the sense of belonging that gives people who belong to a particular religious organization the higher sense of satisfaction than those of us who don't. Whether or not we as secular humanists can hope to achieve the output of the various religious organizations and charities will become increasingly important as the 21st century wears on. If we cannot come together as a community in more meaningful ways, and see each other as those who belong to faith communities do, the question of output will become entirely moot. Then it will become a question of whether or not such a movement can even exist and compete.