Wow AndrewFM, thanks for taking the time to do such a thorough write-up on the game! Just so I don't get all mixed up responding to your points, I'll do them one by one in the same order:
Control Scheme:When I originally started the game, my thought was to have the buttons laid out according to their function (alphabetically)...Y for Yes, C for Continue, just to make it obvious to the player at any moment what should be pressed. I admit that it's cluttered. The 'Z' button is a remnant from an option that I had for player who preferred all the controls on one hand ('X' was used to jump iirc) That's been removed. I've opted out of using the 'T' to bring up hints and tips, as they're all covered in the instruction manual anyhow.
The main buttons you'll use 95% of the time are WASD, arrow keys and the space bar. It's a good call on the inconsitensies in the messages. I'll go through and make sure they are all the same.
Framerate:The version you played through was 24fps, but I've changed that for the final version to 30fps. A little quicker, but much smoother.
Message Callups:It might seem odd to have the message stay up indefinitely, but my logic behind it is that it forces the player to acknowledge it rather than skipping past automatically. My purpose behind the game is not to try blasting through it as fast as possible, rather to take some time and explore all the nooks and crannies of each level, so taking an extra second to read a popup isn't something I'm too worried about
Treasure Chest:Yes, it's intentional, but you only get a fraction of the coins that way. It was sort of an easter egg. There are a couple such things in the game that aren't mentioned just to give the player a little sense of discovering a secret.
Ammo:I've doubled the ammo powerup values for the final version, so it should be highly unlikely that the player would run out. If you do run out of ammo in the first minute or two of the game, you can always pick up the blocks and smash an enemy to try getting powerups. There are other ways as well later in the game, but it takes some experimenting/trial and error.
Keys:They're in the final HUD
Transmissions from Dr.A and Otis:As mentioned in the first post, I've opted out of that in favour of flipping through the instruction booklet maps and such. It streamlines things and lets the player focus more on the game than reading messages.
Underwater Timer:I used bubbles popping to indicate oxygen levels so that it would set itself apart a little bit and be harder to ignore that way (theoretically!).
Relic Collection:The Relic total resets after every five collected since you earn an extra life that way. I tried it out and didn't notice any jumps in numbers. Maybe I laid two Relics ontop of eachother creating the room? I'll look into it.
Light Beacons: A chime should sound when you open them up. Will look into that if it's not the case. Also, the passageways that open aren't always on the screen and require a little investigation at times
End Thoughts:This game is my first attempt at coding/game making/pixelling, so there will always be a huge amount of improvements that can be made. My reason for making the game in the first place was not to be epic or groundbreaking at all.
This game originally was to be a supplement to an illustrated story that I was working on where the reader could follow along as the character explores the temple, and is really only the first chapter of that on-going story.
It definitely caters to fans of NES' Metroid more than any other group, as I've taken a good deal of cues from that game (the rolling action being the most evident of course). If anyone sits down and play through it for more than a few minutes these days with the lack of any sort of real attention span and should happen to enjoy themselves even a little bit, let alone someone who has taken the time to write such a thorough list of improvements (and still enjoy themselves a little bit), then I think that at the very least, I'm on the right track to making better games down the road!
~Edit~ in an effort to make controls more standardized, I'd switched them from C or F to all require Enter to be pressed instead. It means no skipping through messages, but it's definitely more intuitive. And in the long run, what's a few seconds of your day spent reading really??