Lorne talks briefly about SoulStorm on the
Lost Treasures podcast at about
60:30. It was recorded before the press release so he's pretty coy about it.
He does mention that criticisms he heard of Exoddus, that he agrees with, were that it's "twice the gameplay but half the heart" which he wishes to address. He also said the game is going to be "more risky" compared to NnT. "Less of what you knew and more of something else".