Good answers. =)
About Lensol, I prefer to believe that it was a Layan city and Siren's machine army laid waste to it and decided to use it as a prison camp or something.
It kinda sorta makes sense as you go along, but it requires quite a bit of filling in the blanks.
I guess I'll have more clues once I get to Landen and Techna.
About Rhys and Lyle moving to the cave in Aridia, it would make a WHOLE LOT MORE sense if they just moved to Hazatak instead of a dead-end cave full of enemies.