There are certainly some great ideas in Metroid's first outing, but it is plagued by poor design choices that lead to a more frustrating experience than a fun one.
Getting the good out of the way, the first Metroid really nailed the sense of exploration and loneliness the series is known for. Stumbling into a new corridor or finding a new area of the map has such a good sense of discovery.
Unfortunately, the levels are not designed in such a way to be easily explored. Recurring layouts can make the exploration a chore as you keep going back to the same places without realizing. You are going to need to use a guide or keep a piece of paper handy to map out where you have been and points of interest you need to return to. This could be forgiven as just a product of it's time (even though the sequel on the Gameboy was able to implement a map feature to completely fix this issue) if it wasn't for the obtuse level design that constantly hides areas you have to reach in order to progress.
Random blocks in the floor, ceiling or wall can be shot to reveal hidden passages and there is nothing to reveal where these passages are. This leads to a lot of backtracking, blasting away at every surface you can see once you realize these hidden passages are there. I wouldn't mind if there was some indication as to where these passages were (such as slightly off color tiles to reveal their location or some hint in the level design that would lead you to believe there is something behind the solid surface) but there isn't. You're left to just blast everything you see.
The other part of the games design that often leads to frustration is the abysmal drop rate of items from enemies. If you are unfortunate enough to die at any part of the game, you'll be forced to grind enemies for upwards of 15 minutes to recover your health and missiles to attempt a challenge again. This was a common part of design in early NES games (the original Mega Man comes to mind), meant to increase the challenge and inflate play time. But getting another 1-2 hours out of a game by forcing players to mindlessly grind enemies is not what I call fun nor engaging gameplay.
The sequel on Gameboy fixes most of the problems found in the original, but unfortunately exploration became a lot more linear and the repeated boss fights make areas feel too samey. It wasn't until Super Metroid that they finally perfected the formula, producing what many consider one of the best games ever made.
Getting the good out of the way, the first Metroid really nailed the sense of exploration and loneliness the series is known for. Stumbling into a new corridor or finding a new area of the map has such a good sense of discovery.
Unfortunately, the levels are not designed in such a way to be easily explored. Recurring layouts can make the exploration a chore as you keep going back to the same places without realizing. You are going to need to use a guide or keep a piece of paper handy to map out where you have been and points of interest you need to return to. This could be forgiven as just a product of it's time (even though the sequel on the Gameboy was able to implement a map feature to completely fix this issue) if it wasn't for the obtuse level design that constantly hides areas you have to reach in order to progress.
Random blocks in the floor, ceiling or wall can be shot to reveal hidden passages and there is nothing to reveal where these passages are. This leads to a lot of backtracking, blasting away at every surface you can see once you realize these hidden passages are there. I wouldn't mind if there was some indication as to where these passages were (such as slightly off color tiles to reveal their location or some hint in the level design that would lead you to believe there is something behind the solid surface) but there isn't. You're left to just blast everything you see.
The other part of the games design that often leads to frustration is the abysmal drop rate of items from enemies. If you are unfortunate enough to die at any part of the game, you'll be forced to grind enemies for upwards of 15 minutes to recover your health and missiles to attempt a challenge again. This was a common part of design in early NES games (the original Mega Man comes to mind), meant to increase the challenge and inflate play time. But getting another 1-2 hours out of a game by forcing players to mindlessly grind enemies is not what I call fun nor engaging gameplay.
The sequel on Gameboy fixes most of the problems found in the original, but unfortunately exploration became a lot more linear and the repeated boss fights make areas feel too samey. It wasn't until Super Metroid that they finally perfected the formula, producing what many consider one of the best games ever made.