Thanks for the hints, I'll go check every corner of level 1 and that wall in level 3.
Makes sense to finish it first and see how people react before deciding on Steam. One thing that could help with that is short gameplay clips. I'm a professional video editor and cut clips for indie devs, and a trophy hunt in a square-based online game would work well on TikTok or Reddit.
I work through Upwork, so you'd have a contract and payment protection. Happy to cut a free sample from your gameplay if you want to see my style. I also set up Steam pages, so if you go that route later, feel free to message me.
Good luck finishing it!