It would probably be interesting that settlements that are in "ZZZ" mode (waiting an order to produce something) would appear on top of the barre that is visible on the left part of the screen (with the ZZZ flashing if possible).

That would avoid to let a settlement produce nothing during several turns only because you haven't seen that it has finished its production list simply because you have too many settlements to be able to see them all on the barre on the left (and you haven't scrolled down the list to check).

If the settlements in ZZZ would pop on top of the list, you couldn't miss them.