Just beat the game. 100% in 17:36 on Normal.
A few thoughts:
I never really liked how Retro does Metroids. They don't make them aggressive enough in my opinion. When you see a Metroid in Super Metroid, that thing is after you right away. MP Metroids just float around for a bit, dash at you, rinse and repeat. The Metroids in MP3 even stop draining your energy after a short while if you just sit there.
Relating to the 100% ending, I don't think that is Sylux's ship. The ship looks a lot different. I think people are just over speculating, but who knows? Samus' ship looked different in this one, so his could too. Plus, I thought I remembered reading somewhere that they weren't going to include those Hunter's in any other games. I could be wrong.
The game pretty easy, but then again I was on Nornal mode. I think someone mentioned it, but they should have renamed Normal mode to Easy.
I had a little trouble finding my last energy cell. For some reason I totally ignored the one at the landing site on Valhalla, haha.