In Alliance War when people have placed defenders but not joined the attack they are shown in the list of people for that Battlegroup, but without champs, so you can easily see who didn't join yet.
Could you please do the same thing for people in Alliance Quest, based on whether they are assigned to that team or not? That way officers and players can quickly see who hasn't joined yet? You should probably colour them differently, since people can ignore assignment and so the list might show 11 or 12 players in rare cases, but still, it would be very helpful.
Or show it in the assignment screen, that's good too - fade out (or highlight) people who already joined, or something. That's probably a better place to do it.
(I'm guessing I'm going to get a LOT of disagrees from people who sometimes join late...

but we can still see you didn't join, it just takes us time to work it out )