Man < Reapers < Reapers' Auntie
This game is simple and beautiful. The "story" was funny after the Reapers showed up, IMO. I fucked up so badly, I damned everyone else. And the reapers weren't as easy. They'd actually regroup or leave a colony if opposition was too fierce. However, if the pursuit of them was too strong, they'd gain control by hitting weaker, unguarded colonies. It was great.
One gripe though; The mission when they first appear, I destroyed all opposition without claiming the Halo Rings. I couldn't progress without it. I felt shafted. Forced to deal that that nightmare.
The game overall is worth a five. it's simplicity allowed for beautiful visuals and sounds to be created while still presenting a challenge. If I gave you any less, it would be because of butthurt for having to deal the Reapers.