When I first heard we were getting a new 2D Metroid game, I was excited! I didn't care that it was a remake of Metroid II: Return of Samus, and I didn't care that Nintendo had taken down the fan-made remake of said game. I was just excited for more Metroid! Federation Force was not what I wanted at all, so when I got my hands on Samus Returns, it felt really, really good.

I mean that both literally and figuratively. Samus literally controls well, it feels good to play. I was a little concerned with using the circle pad rather than the d-pad, and while true there were a couple little things I'd rather have the d-pad for, the circle pad worked well and I was ultimately pleased with the fluidity of Samus' movement. And, free aiming was wonderful!
But, as I said, there were a couple small things I'd prefer the d-pad for. One such thing was the Morph Ball. It was awkward getting in and out of the Morph Ball with the circle pad, especially during instances such as the fights with the giant drill robot and the Queen Metroid. The other thing I prefer the d-pad for is diagonal shots, but free aiming was a fine substitute.

I was also pleased with the Space Jump and bomb-ladder-climbing. Unlike previous games in the series (like Super), the timing didn't feel awkward or inconsistent, I felt like I got a real handle on when to press the buttons and when to move. The grappling shot still felt slightly wonky, but still improved from previous titles.

But despite the overall good controls, there was a lack of variety in both enemies and environments. There are only a few different enemy types, and the only progression any of them have are color swaps that simply take a few more shots to beat. The aesthetics and designs of the enemies are fine, and fitting for Metroid, but it got a little tiring finding (basically) the exact same enemies over and over. That's coupled with the environments. Each area looks mostly the same, they just have slightly different colors and some different background music. I couldn't tell you the difference between Area 3 and Area 5.
But, to their credit, they managed to create a fitting exploratory atmosphere despite the lack of variety. There were several instances where I really had to search after finding a shed Metroid skin, and I had to use my wits to solve problems to get the upgrades (which were mostly missile expansions, but we'll get to that later). I got lost a couple times, but mostly only early on and it ceased being a nuisance once I got the game down.

And speaking of atmosphere, my favorite was perhaps the final fight with Ridley. The storm and the way the sky looked was brilliant, and the fight itself was enjoyable, although I wouldn't wanna do it (or any boss fight, really) on high difficulty levels.
The other two major bosses weren't as enjoyable as Ridley, unfortunately. That comment about higher difficulties, and the one before about finding mostly missile packs? Well, you see, even on Normal, these bosses do entirely too much damage, to the point of the game being outright unfair. Energy Tanks (health packs) were much more scarce than missiles, and that doesn't balance well with the absurd amount of health each attack from the bosses do. It was especially noticeable during the drill robot fight where you're required to use the Morph Ball, and that also plays into the awkward Morph Ball controls.

But overall, this is a very good game and it was largely successful in delivering a good Metroid experience. There was a good exploratory sense despite a lack of variety, the controls feel good and are for the most part fluid, and it really just FELT like Metroid, and that felt good. I'd give Metroid: Samus Returns a solid 8.5/10.