I think i would prefer the camp meter, it would make the game easier for the players when an admin is not on the server, the second solution requires admins on the server which we dont have many hours a day + there's a lot of newbies on the server making them use the radar to go get the bomb could be hard and even harder with the ones who doesn't understand english. Some players new to the server don't even understand how to open the doors.
Once and a while i meet players that sits in ct spawn or vent with the reason "im guarding the bombsite" or "im guarding the bomb" which a lot of players find annoying. Telling the players that the ts team should plant puts one team as a defender and the other as an attacker, imo this rat map is more of a fy map, the ct and ts team should meet up and fight each other, i think it's makes the map more fun. As doggie said "we should encourage moving at all times"
Camp meter set on 15 sec sounds good to me.