I think you're spot on in your contrasting of the two, in fact I could not agree more. I don't think Lennon is Poch's final intended solution for the position at all, but rather a stopgap. He of course wouldn't be looking to acquire Rodriguez if he were content with Lennon. Believe you me my friend, if it were all up to me, I'd bring in another left winger in a heartbeat. I know you're new here (and would like to reiterate that I think you clearly know your shit and I value your opinion rather highly), but believe me I've been beating on the left winger drum on here for well over a year at this point.
However, Lennon has done well enough to provide that stopgap, which is while I don't like it, I believe we'll end up going ahead with what we have at winger unless Koeman does indeed decide to chase Chadli. But I really don't think Holtby would be content with playing wide, and he seems to be very excited with the way Poch wants to play . He's said he doesn't even prefer playing CAM, let alone as a wide option. So while it seems you may prefer the lineup, and preferences aside it may even work the best, it's still nonetheless one I highly doubt we'll see after all is said and done at the end of the window.