Heck of a map
You had room however, so lock up the top two rows to avoid having to move the status bar. IMO too much ore available as starting resources. Maybe make the player dig it out and protect the source. The phantoms were a none issue as the two coils provided took care of them after maxing range and all other targets were inside a AC envelope. Make 'em stronger (max creeper) and place them ABOVE the coils.