Lightning network was created mostly for small payments. For example you open channel with some product shop. Or with your friend. Of course, you're able to use others channels but in that case you must pay fee as you know (and also it is risky idea. hackers don't sleep). So someone will close 10 channels per year, another - noone. So i took average number.
I don't know what it was created for and I would say it doesn't really matter. All I am saying is that it is completely possible to use it for that and there are costs if you don't use it. But we will see. no one can know an average number when the thing doesn't even exist yet.
Lol, this is some kind of exisiting bank system. Trusted nodes == banks.
There us a reason I called them well known nodes and not trusted nodes, because trust isn't necessary in a Lightning Network, that is the whole point of it. If trust was needed, we would just use banks instead.