To play out a few more possibilities in my head based on some of the info here...
This could be played completely straight and result in Itsuki being ruled out of the Fuutarou bowl once and for all. An utter BTFO. I do wonder what Fuuts would think of Itsuki once she is unmasked.
The rejection of Rena might force Itsuki to become more upfront in her dealings with Fuutarou.
The Rena rejection stuff will set up Nino or Miku, and maybe Yotsuba, to make a move.
It's probably too early in the plot for it, but would have been cool if he had said something along the lines of, "The only girl I want to figure out the identity of is the kisser." That would have set some interesting stuff up.
Negi loves playing with expectations based on what other writers have set up as defaults in the past, so I really wouldn't be surprised to see him play this completely straight as part of Fuutarou rejecting Itsuki and setting up an ending with 1-4 (probably Nino, but whatever). Or it could be played straight and lead to the opposite result. Fuuts still just doesn't seem interested romantically in Itsuki, whatever she feels for him. He thinks of Yotsuba as a friend, Miku as a supporter, in a holding pattern with Ichika, and uncertain what to do with Nino, albeit not really unreceptive either.
I still want to see what Nino does this arc. Every major arc like this always seems to come back to her and her feelings in the end.