I echo (ahahahaha) the thoughts of Paladin, KDR, and HC. Once you beat Chozo Ghosts and Grenchlers the first time (aka MINIBOSS EVENT), they're largely OPTIONAL to fight afterwards (save for specific objectives). Really, they're all "short work" once you have a proper strategy. Or just MORPH BALL AND JUMP YOUR WAY OUT THE ROOM.
Even the final boss in Prime 2 involves a strategy that takes advantage of one of your later abilities, which I think Ian has yet to figure out and would eliminate earlier complaints from threads of generations past.
Boost Guardian was definitely difficult the first time, as you're assaulted by time pressure due to dwindling health. But he was STILL predictable. The urgency of the fight and the view just made it difficult to notice the proper cues/reactions.
Dark Space Pirates are waste of time, however. They've got more stamina than Chozos or Grenchlers, and usually live to the end of the encounter's time limit, depending on how many you have to chase.
WEAKNESS POPPING UP IN THREADS EVERYDAY.
TIME TO CLOSE THIS ONE.