I think the problem is that players like to get the cv as close to shore as possible. no matter how many times Someone wants to keep a further distance the majority will want to bring it in closer. People will drive the cv to the shore to matter what opposition so they can get to the fight quicker.
Adding mines or better shore batteries will do little in my opinion. The limited field of fire from a shore battery is routinely ignored and the carrier is driven into it all the time. It is driven into PT spawns all the time with no regard to what those little purple arrows mean. Making coastal defenses more deadly will not affect the desired result.
The desired result I assume is sending a CV to attack a base with better chances of the carrier's survival? to promote a low alt fight? or a shorter distance fight? For base capture purposes? If any of these, instead of "this segment touches land" maybe "this route is too close to shore?"
Of course, the majority wants to drive the cv up as close as they can, so is the majority correct because that is what is fun for them?