Ok. I managed 73 items. I have all main items except the Screw attack, and possibly a fifth misc item.
Most of my observations are items. First...the Space Jump...its practically impossible to use. There's one really tricky area that either requires that or the Ice Beam (or both) that I can't get through and I think that's where I need to go.. Second...the bomb jump makes it extremely easy to sequence break. And it doesn't seem like water lowers the power of the jumps either. I got the Ice Missile, Hyper Grip and Plasma Beams right after the High Jump Boots. The Speed Booster...extremely difficult to rocket upwards. I can think of at least one power up I can't get because I keep jetting to the right each attempt. I also noticed some powerups are through a narrow tunnel in mid air, and you can't actually get into the tunnel without falling. Also, once you can phase through walls...its possible to speed through entire sections of them. What comes to mind most is by the spaceship. You can phase through the wall straight to the escape sequence. Also...is there a third metroid upgrade? Because there is one barricade it won't destroy and its already big.
All in all I did enjoy this. It has a true metroid feel to it.It just needs a lot of polishing over.