TPTB have said they'd like to have Zatana. If they by some miracle got MR to come back for an episode or two I wonder if they'd pull an Identity Crisis on Lex. DC canon supports GA, Flash, and BC joining Zatana in mind wiping villains who discovered secret identities
That would make a really interesting episode. If they had the ability to, I don't doubt that Oliver at least would be behind a mind wipe; I really can't think of what else they actually plan on doing to Lex if/when they find him. I am rabidly against the idea of a Lex mindwipe (or an
anyone mind-wipe, but especially Lex), and I'm sure they'd mangle the moral implications of it, as always.
I just don't think he cares about her in the same way he does Chloe, Lana, Pete, Oliver, etc. I still see Clark as seeing her as "a friend of a friend" rather than a genuine friend. I think he feels comfortable around her but I don't see him losing any sleep if she decided to move out of state.
IA. The way Clois interact reminds me of sort of how you'd interact with a coworker or a sort of distant cousin. There's something connecting you and you like each other well enough, but beyond that, the only bond there is is based off moments, like their three hugs last season. That's enough to firmly place you in the "friend" column, but there's no close emotional bond. When you're physically close, you're "close," but when separated, it's kind of just a "Oh, yeah, that person...." YMMV.
I do wonder how much this will change over the course of the season, if at all. From what people have said in interviews (ED saying Lois is oh-so in love with Clark aside), it seems like this joking, condescending type of relationship is going to continue. I really don't enjoy it, but from all we've heard, it seems like they're keeping it "funny" (except for the anvils they're going to drop on our heads).