At first I was a little "I don't know" on Amy in the red hair (only because one of my favorite fanfic fancasts her at their alternative-Lana.) With that said, the red-haired Lois doesn't bother me. She was red-haired from the beginning of the Byrne during and even through their wedding.
The Jimmy into Jenny has both positive and negatives to it. Positive in the idea that Lois is mentoring another female in a career path that has seen fewer women enter it over the years. On the negative, someone did point out how it would be a potential romantic rival (couldn't they just do that with Cat? It's been done before in the comics and suggested done in our favorite show.) Quite honestly I'm taking this rumor with a salt lick.
CLARK: No. I'm just worried I'm a jinx.
JONATHAN: A jinx?
CLARK: Yeah. Let's face it, ever since she's known me, Lois's been kidnapped, frozen, pushed off buildings, almost stabbed, poisoned, buried alive and who knows what else, and it's all because of me.
-"Contact" (You're not her jinx, you're her blessing.)
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