Expansion as the player base grows

So obviously it's a bit early to be discussing the expansion of a game that is yet to be released, however I was curious if there were already ideas for the future of Path of Exile if it completely blows up and has the player base any staff would love to have.

They stated they have a long development road map. So they already have plans for at least one expansion, if not multiple.

"

There is a long roadmap of free expansions planned, and we anticipate releasing both feature and content upgrades periodically for many years.

Does that answer it?

I think they said Act 3x is due in September with a new act every 9 months approximately.
Also releasing small weekly content patches for gems and uniques etc.