I believe this was not a random crime; the perp is someone familiar with Evansdale and with the 7 Bridges area; and, the perp is probably someone known to one or both of the girls.
I don't think LE is totally clueless, and believe they have their eyes on a suspect(s) but are waiting for evidence to be processed. The perp may be in jail on other charges, giving LE time to work their case without fear that the perp will get away.
I do feel the girls made it to the lake that day, and the bikes were left there at the time of the abduction as opposed to being staged. I do not know what route they took to get there.
I believe the girls were taken directly to 7 Bridges after being abducted, and were killed on the same day they were abducted.
I have no definite theory on the motive for this horrible crime, but I am not convinced the primary motive was sexual. I think there are other valid motives that should also be considered as well.
I don't know if both girls were targeted, or just one of them.
I don't believe the perp will turn out to be a local RSO.
I think that when the perp is named, we won't hear the usual "I never would have suspected him" or "she would never do something like that" or "they were good people." I think we'll hear "there was always something off about him" or "she made me suspicious" or "they've always acted a little strange."
All JMO, MOO, IMHO, etc.
ETA: And I still don't know what to make of TG's sighting of two bikes on the trail. But I do not suspect him of anything connected to Lyric and Lizzie.