User blog comment:Ducksoup/Sprucing up your Main Page: Introducing the Hero Image/@comment-4129195-20150227200457/@comment-24739709-20150227214746

In order:

Nope - this is mainpage only.

OK - will add this to the list.

You can resize your image locally, but since this is a beta, we didn't include the option to resize it in this release.

I don't know what you mean by "sponsored"?

No GIFs right now, unfortunately. Hopefully that's a change we make in a coming update.