Ah, you're right! There should be a way to delete nodes.
A scoring system would be fun but I'm not quite sure what to minimize, least nodes or least moves?
Thank you for the feedback!
You're right, I must have overlooked something in the algorithm for deciding the action. Level 4 is the intended result (try placing your nodes 1 block further).
I would've liked to have an indicator, however the 3 block limit was added quite late and I knew it would take some time to add it properly to the rendering code, so I had to settle on a texture change.
Again, thank you for giving the game a try and for excellent feedback <3