Yes, I can answer them.
On both question I have to give you a no.
You can't activate to show your signature on every post you make, because it isn't even seen with pleasure that some people include it with every thing they write.
(Some still do
It stretches the pages too much and causes too much scrolling over repeating pictures.
This is also why you can't activate it within the "QuickPost" field and have to use the quote or reply buttons.
The second isn't available as well. And another problem is, that once you activated it, while opening a thread, that you can't deactivate it anymore and recieve mails until thre thread dies.