I liked this quite a bit. Maybe it’s because I haven’t seen Sif’s character explored anywhere else in Marvel-verse, whether it be the comics or MCU, but I was just glad to see her front and centre. I liked the art, and I liked the tie-in to known Norse mythology (the concept of berserkers). Other stuff, I think I’d have picked up on more if I was used to the version of Asgardian mythology created by Marvel, but it still worked pretty well.
I think some people talking about her just being bloodthirsty and so on missed all the points where she held back the other Berserkers and forced them to behave fairly. So the spell gives her “licence” — but she fights that even before she knows anything about it.
I did like the bits with Heimdall, too. Also nice to see Asgard with barely a trace of Thor. (I like Thor, but he steals the show.)