Common Catalogue Patterns
Below you'll find a collection of reference implementations for non-obvious problems you may encounter when implementing some restrictions, rules or anything more complicated than 2+2=4.
Let's take a look at how T'au Empire Commander has a default of 2 weapons:
The group itself has no default set, but instead what happens is, BattleScribe automatically takes Burst Cannon and Missile Pod (because of min 1 constraint) and then no longer enforces these constraints because modifiers come into play.