Valkyria Chronicles 4

• Units rank up by getting RP. RP is gained solely from being activated in battle. 1 activation in a story battle gives 1 RP, normal skirmishes give half, hard ones give 1.5x. Notably, it doesn't matter what the unit does, just that you took control of it.

• The game's explanation of squad stories is misleading if not flat out wrong. Instead of using those units together, you just need to use one of them until they get 20 RP, which for most units makes them a corporal.

• Squad stories require you to have all the characters in them, so if you have a unit go from private to corporal and don't get their story, you probably need to wait.

• Class levels don't matter that much unless they have a special bonus. Level 11 makes a class elite, which among other things increases their AP and gives access to improved equipment, so once you've unlocked a potential for each class beeline that.