I think the idea is super cool and creative! my advice would be to make it more immediately recognizable where the connections of a block are by switching the artstyle so the colors don't overlap. The game gives me mini-metro vibes so maybe something like that? if you do want to stick to the pixel art I would suggest making the borders a different shade, if you want you can use a site like coolors.co to get some good colors.
Despite the game being cut of, I got to play it because i realized i could drag out the html with developer tools and play it in another window.
Here's the link for anybody that wants to play it for now!: https://html-classic.itch.zone/html/14525561/index.html
However, you should still try fixing it. To do that you can go to the game, click 'edit game' on the top of your screen, scroll to the part that says 'Embed options' and mess with the settings till you get it right.
My Highscore is 44 for now :)