Hello there!
1) Oh, the idea is that if they are more than 5 units of distance, the new link changes color to show it is not possible, so you can and should connect as many computers as possible, as long as they are close enough.
2) It is possible already, through the settings menu.
3) I'll work on that! I was thinking maybe adding some ballon with an alert nearby, or maybe making the connection "broken", sort of like two plugs far apart.
4) Neat, currently I just change the "wifi waves" on regions to red in order to show there's a buggy connection in that region, but I can think of some other alerts to indicate new machines.
5) It's a nice idea! At first, that health bar was supposed to be a "general internet satisfaction meter" and it would involve many parameters, such as bugged connections, computers able to send all the data they had, expectations of a bigger network through time... but it got a bit too unwieldy for a jam game so I made it just about bugged links and non-connected computers.
Thank you so much for the feedback!