I think that the minimap should have blue squares on it, instead of green ones, if there is a member or your army still on that screen, so instead of wandering around all your completed screens in search of some people left out, you can see where they are. This would also help in cases where you thought that you still had a unit (ostensibly a high level one), which died but you didn't see it die, as instead of hunting around all the screens for it, and searching again and again due to thinking that you must have missed it, you can simply visit the 'blue' screens and check.

For people who may say that they wouldn't leave soldiers behind - some peoplse are bound to, it's helps with the second point again, for those who aren't sure (no blue dots on map mean that that soldier must have died), plus some people may leave some behind in order to use other soldiers on other screens (fodder/levelling up).