Akua POIs: ruins tower and activator

Every time I start the game from scratch, I find something new in small details. Especially as of current v1.8.1X patch and better version of the PDA. E.g. I've never thought about digging around small wreckages, now the game has a hint

Anyway, the things in question are as follows:

1. Activator POI.
   I've already completed the Tales of Tash story line on the starting moons in my previous starts collecting all 16 datapads. I'm still not aware of those small "Activator POIs" found on those moons. Do they have some function or is just a cosmetic mysterious POI?
2. The ruins.
   One knows about this scattered POI when doing the raptor hunt side quest given by Talon. Nothing interesting there except for a few barrels with 1-2 items of food or alien parts. In the center of the ruins there is a "tower" with a motion sensor on it's top. I could not figure out if it really does anything. A little bit lower there is an alien plate, I was expecting it to start glowing after activating the motion sensor, but no, it does not.
   So what does this motion sensor do, did I miss something? Or does it have anything to do with some quest? I happened to destroy it with a multi tool because of misclick. The whole building can be torn apart, does not have any protection on it.
3. Spoiler: Later progress

   Right in the center of all moons there is a ship with a teleport to Omicron, a planet we are well aware of during our older playthroughs. This ship has the generator room under a pin, I did not happen to find this code. Yeah, I know, the wall can be easily destroyed with explosive and there is nothing that interesting behind it, except for some alien-scorpions and the core, but would be interesting to know where this code is hidden.

I've searched the web and this forum, could not find any clues.

 

3. That one was pretty obvious, found on the station nearby

 

1.most of these are cosmetic i think to drive the alien world point home.

2.the tower was used for a quest in the past where you had to get up and the plate would trigger. the motionsensor is just a left over from it i believe.

 

I remember that one, yes. Used to be the 1st or the 2nd quest for Talon. You are right, looks like a leftover.