Hmmm... I would actually say the game is a little unbalanced in terms of difficulty.
It starts of pretty moderately difficult, when you are underpowered and haven't accumulated too much health or powers. Then, it gets progressively easier to the point that you can tear through basically everything without even looking at the screen by the time you've unlocked all your powers. It feels great because you remember how vulnerable you were and now you're an unstoppable God, but it also feels kinda like okay, the game's done now.
Then again, the bosses kinda feel like a whole different game almost, much more focused on timing and quick reactions and stuff, they can rip you to shreds in seconds if you don't know what you're doing.
I got on fine with the bosses, I actually found them fun to figure out, but you gotta actually TRY you know, you can't really take them on just spamming and tanking hits like most games, you gotta do the right stuff.
That's fine by me, but it definitely feels unbalanced compared to the rest of the game, you don't need a similar level of concentration to play through the actual game compared to the bosses.
As for the EMMI or whatever they were, I mean I don't really think that aspect hit with me. Avoiding them was basically pointless because as soon as you die you get another chance right away. I never felt... AHEM... DREAD when encountering them because they caught me ALL the time, a million times each, like they go straight for you and then you get another chance, so it just felt like... Okay grab me fine, I'll just try again, no biggie...
Overall I think it's a very good game, I would actually put it on par with the other two, like Super Metroid and Fusion, but for different reasons. I think the combat, the movement and the pace of this game are better than those two, but I think the other two have better level design and have more memorable like environments and art styles.
So yeah like a probably solid 7.5/10 from me, not quite great but very good. I'd maybe say Super Metroid deserves an 8, but only because it came out like 30 years ago, I actually had more fun with this game but I doubt I'll remember it as much a year from now.