Distances and weights will at some point hopefully differ from one map to another. Why have the gravitational information of a map displayed at the beginning of each map, if it's not going to be implemented in some fashion. Maps with a lesser gravitational field, may ultimately effect the range of our Seismic. Less weight > less pressure > less seismic wave range. Will be interesting to see what they do with it, if anything.
While agreeing with most everything untamed has said, i'd have to disagree with being able to detect mechs any further than what is already being shown. Simply put, it would just be WWAAYY too op. Maphack basically. Technically you are right, but it's just a balance issue. If everyone had one it might be a different story though.