Is Jeff still worth it?

I’m debating whether to spend keys for Loki this week or Jeff next week. I don’t have Arishem, but I think Loki looks like a fun card. I see Jeff in almost every deck list I look at though so he seems pretty essential to have.

I don’t have pixie yet, but I do already have iron lad so this week might be a better value. I’m around CL 1500.