Thanks so much for taking the time to play Olec, that is unbelievably cool that you got the game to work on the Steam Deck!! This version of the demo is not at all optimized for any platforms other than what they have been released for (Windows, Mac, and Linux while on a PC; either with a mouse and keyboard or gamepad), since the game has not been tested or designed for other platforms, so this is amazing news. On that note, thanks so much for sharing that you identified some areas for improvement with the Steam Deck controls. The demo will always be available here on itch.io for PC, but before the full game is released, I will absolutely look into the control schemes available, and will ensure that the game is thoroughly playtested so that it works seamlessly for players on the Steam Deck.
Given the different resolutions that mobile devices and the Steam Deck have, you can look forward to optimized visuals for those devices when versions are made for them in the final releases. They are not available at this time, so I'm sorry that you had some difficulty with the fonts, but I eagerly anticipate the later releases for mobile devices where the text will be larger and many more accessibility options will be available.
Stay tuned for more updates, I am super excited for bringing the completed demo and full game to you all too!