Things I've been wondering about as a new player

Thanks J! This clarifies many things!

I got something more that bothers me...

Today I got my first 2 dark side ships, and I unlocked this achievement. But I'm afraid to collect it as I fear it might dissapear, and not count in the actual ship building materials once I unlock them. Same goes for the fleet arena tokens. What should I do? Should I just let them hang there for now until I unlock ships?