1.

Yes, with the new permissions system you can choose which users (including guests) get to see the banner island inbetween post 1 and 2.

2.

There is no standard solution for that. I have made it as a hack for a different forum, it's not too difficult.

3. As I said, depending on groups you can display banners or not, donations can put users in groups etc.

[Linked Image from siemons.org]