The first playthrough is fun, though nothing super special. The real fun comes from repeat playthroughs. Really, your first time through is just a warm-up to get you familiar with the world and controls. Once you know where everything is, you get to test just how far you can push the bounds of the game with how many abilities you can get early or skip entirely, your pick. It's up to you how you want to go through the game, and what crazy kind of sequence breaks you can pull off come down to your skill and your outside-the-box thinking.
The two major detractors of the game are the controls and the bosses. I'm more used to the GBA Metroid games, so the floatier physics took a bit of getting used to, though I ended up gaining an appreciation for them likely thanks to how they help make a lot of sequence breaking possible. The controls themselves also took a bit of getting used to, and while I understand there's plenty of people who love Super's control scheme, it felt a little clunky to me. Having to mash Select to choose what you fire only gets worse as the game goes on and directly contributes to the sort of floundering feeling boss fights tend to have, as hitting the button one time too many or not enough can end up making you miss the chance to hit a boss's weak spot, or just generally do something you don't intend (“Oh oops, didn't mean to try and Grapple Beam the boss. Oh oops, there go a couple Super Missiles, meant to just use regular ones”). The bosses themselves also felt a little clunky to me. It feels like you can't dodge all of their attacks, and so an element of success is taken away from skill and given towards simply how many Energy Tanks you have. Like, on my first playthrough, I found every boss to be a joke up until Ridley, who killed me over and over again with his erratic movement. On a repeat playthrough, I got to Phantoon early and died to him over and over again, largely because of cheap hits from him just appearing on top of me. Same thing happened later on in that playthrough as I went to battle Draygon with significantly less Energy Tanks and general equipment than my first playthrough, and got decimated because there's no way to tell whether she will swoop at you or not until she does it (and I could skip all this headache if I had the Grapple Beam, but I didn't, as I was trying to skip it).
Just a bit of a rant, but the rest of the game is excellent. Lots of freedom to explore, yet I never felt like I was wandering around unsure of where to go (and also never felt like the game was expressly pushing me down any one path). It's a hard balance to strike, but it's managed here it phenomenally. Super Metroid is a game where you'll constantly find yourself asking, “Hmm, I wonder if I can...” and the answer is always an emphatic yes. But you've gotta be the one to do it. It's always up to you to figure out how to sequence break and to actually pull it off, and that's what makes it so satisfying. It's that unique feeling that allows Super Metroid to stand apart from similar games, and what makes me love it despite my issues with its controls and its boss design.