Kevin... When I first read this thread, I thought that was what you were after... Free basic services, with payments for sellers. Makes perfect sense to me that way. Then came along suggestions for a middle tier. Not sellers, but a few enhanced services. I don't have any problem with that either provided the enhanced services don't displace what most of us do here before they existed. At that point in the thread, the only thing that bothered me was the suggestion that posting pictures would be considered one of the "enhanced services". That's a problem because this is such a visual hobby.
Then somewhere down in the thread I got twisted around into thinking that you were contemplating charging for even basic use. That's when I posted, and I apologize if I misunderstood.
What broke the advertising model is the cost of reliable services. If you need 10,000 people to attract advertisers, and those 10,000 people (not to mention the advertisers) have to be served reliably, then you need sophisticated systems, power backup, high quality software with maintenance contracts, etc. As it turns out, all of this costs more than you can recover selling advertising space! This will remain true until the cost of mounting reliable systems comes way way down. I don't know when that will happen. In the meantime, advertising floats some percentage of the enterprise, and I guess you have to make up the difference by selling "enhanced services". I hope it works.
Thanks for listening