Clawdy, yes totally agree.
It's drawn me in more and more each week, and, grisly scenes aside, I think the experiments with time reversal plot has been interesting. Still confusing to me on occasion, but it's got clearer now I'm used to it.
Williams brothers on 10 x better form here than with their Liar, that's for sure. 
- Are we sure Elaine is the serial killer? Yes, she's offed Jonas, but he could be her only victim.
- She said to her mother's ghost(!) she wished she could turn back the clock to being blissfully ignorant of certain memories again (indicating that she'd just found out about something?), her eyes were now open, "You're proof that memories aren't something you want to protect" and "You just let it happen"...
My (no doubt way off!) theory is that she perceives her mother to have, wilfully or otherwise, turned a blind eye to her father abusing her (He 'apologised' to her at the prison visit, causing her to storm out. And she obviously hates him, from what we've seen).
In last week's prison visit (so chronologically the 2nd one), he very pointedly looked at her when asking her if she'd even burn his car along with anything else he left her in his will, again causing her to storm out whilst telling him to hurry up and die. Could abuse have always taken place in it?
The hospital scandal 20 yrs ago: maybe, after the trauma of her father murdering her mother (perhaps because she finally discovered, or already knew but finally confronted, his abuse of their daughter?), Elaine was treated as a hospital inpatient by Jonas.
Who, like Isaac, has some weird perversion and films his patients reliving their distress for his own twisted kicks (to share with each other? With a wider group? Online?).
That is what Elaine has stumbled upon, hence why she decided to mete out her own payback.
Probably completely wrong, and I hope so, because CSA (and skewed portrayal of mental illness, for that matter) seems to be tacked on to most shows at the drop of a hat.
- Am really embarrassed that it's taken me 5 episodes to realise why it's called "Rellik"
("Killer", backwards).