So while these have seen some pretty prominent usage among high level players with Ronahn's Enhanced Sensor Beacons, I'm concerned that the default form is heavily underutilized. The upgrade is like 200/50 just to grant vision in a radius, which while useful it's also absurdly expensive.
So my suggestion is as follows:
Ronahn's Presence no longer grants Sensor Beacons for Free. Offers friendly unit concealment and detection of enemy units.
Sensor Beacon cost reduced to 125/25
This would make it a more attractive upgrade for strategies that don't feature Ronahn and it's a slight nerf to a lot of Ranger/Ronahn builds that seem to be rising in popularity since they now need to devote the time and money to take advantage of the beacons.
As it is, Sensor beacons are pretty useful for a few things, but without Ronahn the cost is too prohibtive. Likewise, it's a little too good to get a 50 power upgrade for free just because you took Ronahn's Presence ability and to my knowledge it is also the only Presence ability that lets you shortcut through tech like that.