I really enjoyed this game/synth/experience. I love the chill soundtrack, the trippy abstract visuals, and the bold and unconventional color scheme. Piloting the lunar lake and going over the waves is very enjoyable in itself. The trading gameplay is basic and unchallenging, but serves the purpose of motivating you to get out on the lake. The accessibility of the interface is quite good, although the gameplay could be more interesting when playing without graphics. And, kudos on implementing an actual tutorial. Ahoy!
In the spirit of improving an already excellent game, I offer some feedback.
Playing without graphics at first, I really struggled with getting myself pointed toward my intended destination. I think this could be alleviated with more tutorial and explanation. In particular, explaining that the "beeps" mean you are pointed at a port, and that the "Target" action selects the signal you are pointed at. For a very long time I thought the beeps were just musical embellishments, and wrongly guessed that "Target" was supposed to turn my ship toward the target I had selected with the "Next/Previous Target" actions (which would be a very welcome feature), but didn't seem to be working right. I don't think I would have ever figured it out if I hadn't played with graphics turned on later and noticed the beeps corresponded to the "fireworks".
Clearer audio feedback when you are running into the edge of the lake would be appreciated. There is a sound effect, but I wrongly guessed that it indicated an interesting object or landmark, so I actually tried to move toward the sound for a couple minutes. I didn't figure out what was going on until I turned on graphics and noticed that I wasn't moving and the dots ahead were black. Maybe there could be an intervention via TTS if you keep running into the edge for 15 or 30 seconds.
Probably the most fun part of the game is going over the big waves, but you don't get the same feeling without graphics. I think maybe I could tell a difference in the music when going over a wave, but if so it was subtle. It would be great if the music could change to evoke the feeling of anticipation of seeing a big wave ahead, the growing excitement as you rise, and then the rush of coming back down.
The tricks system is a neat way to add gameplay interest to travel, and to participate with the music. But if you're playing with a screen reader, the musical experience is somewhat spoiled by the TTS butting in to tell you that you got a measly few credits. It would be better to use music/sound to communicate how sick your tricks were, and instead of giving credits (which aren't really needed, and doesn't make narrative sense), maybe performing tricks could give you a speed boost.
The bottles were an enjoyable diversion from just going straight from point A to point B, but it's an aspect of gameplay that blind players miss out on because of the (apparent) lack of audio cues. Although I'm not sure the mechanic as it currently exists would be enjoyable if playing without graphics, because the reward may not seem worth the hassle of stopping, orienting yourself to the bottle, then orienting back your destination again. Maybe a slightly altered mechanic, where bottles can appear on either side of your ship (indicated by a music change in the left or right stereo channel), and you can strafe or lean over to grab them as they go past, without changing your heading?
A technical issue I encountered (using the Windows download) is that the performance of the music playback gradually gets worse over time, perhaps indicating a memory leak. The music is fine at first, but by 15-20 minutes it is noticeably stuttering, and eventually after another 15-20 minutes or so it seems to give up and die. It seems to revive slightly while docked in a port, but not once you are back on the lake again. The graphics, interface, and TTS remain just as responsive, only the music is affected. Quitting to the main menu doesn't fix it, but restarting the application does. As a developer I know this sort of issue is easy to miss because we usually don't play our games for long stretches during development.
Anyway, I hope this doesn't come across as too critical. I really enjoyed the game. I played it for nearly two hours, and then spent over another hour thinking about it and writing this feedback, because I liked it enough to really care about it becoming even better! Excellent work!