The Karen and Frank stuff was great. Frank's single mindedness does feel more real here than it ever did in the comics. He is fleshed out and emotionally understandable as a human being. Karen gaining his respect says a lot to the audience... Which again worries me about the ultimate fate for Karen in the show's life.
Elektra is too much of a temptation on so many levels for Matt. She does bring out the worst aspects in him, takes him to the edge. That said that interrogation scene of the guy that encrypted the Hand ledger just looked so much of what I expected and dreamed a DD show should.
Matt and Foggy... I fear we are seeing the seeds of this bromance break up. Which I suppose makes Elektra Yoko?

Real talk though, Foggy is covering for him and feeling the pressure. Foggy is sort of an Alfred that, rightly so, has not come to a zen like acceptance of what the hero is doing but Alfred doesn't have to deal with Bruce continually lying to him.
Elektra says some harsh truths to Matt here about himself and his crusade. No pun intended, that man has a blind spot. Which... Is what makes the character so interesting and rich. Cox's performance doesn't hurt either.
Those trains of soil and that giant hole, man... Bad juju. Which brings up... Given that the Hand injects major league elements of the supernatural, and no not "magic and science is one and the same" but straight up mysticism and horror elements I have to wonder how all that is going to mesh with the street level vibe that the show has had from the start, Matt's powers notwithstanding.