We’ve done two mini campaigns so far; one in the Pacific and another in North Africa.
Each player has a piece that represents them (one for the Axis and one for the Allies); it has certain abilities and begins with a set rank. Once you gain enough VPs (through victories, destroying units, rallying troops, etc) you move up a rank which mat entitle you to more SAs/CAs, improved initiative, etc.
At the very least it gives some continuity between games instead of a series of unrelated events not everyone cares about; if you’ve invested time into your squad then you (usually) are much more interested in the games; and even if you technically lose, if your squad does well you can still count it as a win.