Right now I can not click on a connection and see where it goes, and the delete button is only there while i hover over it. This gets unusable super fast when multipe connections overlap.
I suggest:
* You treat connections as first class citizens that can get focus by a click on them. This means I can move to the delete button without loosing focus
* You change the color of the avtive connection, the one that has focus - which allows much easier to follow one specific connection when they overlap.