Just to muddy the water... There's a bit in the front of the rules about base footprints & preferred model counts. Basically as long as the footprint is the right size, you can knock up a scenic base using a few less models, i.e a regiment of 20 can be done using 15. (Admittedly mine are 12 each, should sort that out)
Which means you can, in theory, spread the minis a bit further by using them that way. And as whole units come off the table, not individual models, it doesn't matter that they're stuck in place.
However this does mean you have to store a single lump on a 125mmx100mm base instead of several, easier, smaller 25mm squares.