speaking about puppets, what about Kosh? I was struck by how much I cared when he died.
How about the "other" side of Federation space? Away from Klingon, Romulans, Cardassians, except as occasional guests and give us a bunch of new aliens.
Or how about a ship that pulls a "Bozeman" and turns up a century or two after leaving and how the crew of this ship adjusts to it's new time.