I think WFC had this same unusual/redundant set-up as well...

King of the Scrap Heap (Gold/100) — Reach max level in all four classes
What Prime Directives? (Silver/25) — Unlock Prime Mode
If I recall... the moment you reach "max-level" in your fourth class, you gain Prime Mode. So why have two trophies/achievements that are for the same thing?
Isn't that true? Or am I missing something obvious?