Using Pro Sites to offer simple WP Forum Sites

I'm exploring the idea of using Pro Sites to offer simple, niche WP forum sites to individuals, local civic groups, small advocacy organizations, etc.

The primary product would be a choice of a few layouts with forum software already installed.

My idea was to appeal to those who'd benefit from the interaction offered by forums but didn't need more than a few static WP pages beyond that. Perhaps a simple sales or donate page.

I had a couple of general questions I thought I'd ask of those more familiar with Pro Sites and Forum software than myself.

1. Is Pro Sites best for a project like this?

2. Which WP forum software would be best? The latest bbPress appears suited for this task but Simple:stuck_out_tongue:ress appears to be a better "all in one" solution.

3. In order to keep it simple, I was thinking of offering a choice of a "free" ad-supported site or a simple no-ad version for a small monthly fee. Is there a way to implement this in Pro Sites?

4. I'm reasonably literate on WPMUDev's offerings, but which ones do the more experienced users recommend I use on the back end?

Thanks in advance for your suggestions!