Rico Flores seems like a great kid and he is a very hard worker. Exceeded all expectations this year. He is a good young WR that I hope stays with the program.
But I don't think he makes or breaks the program. I don't think any of the WR's in the current room do. The WR room held back the offense so much this season and couldn't get open against good defenses. You can't win consistently without completing passes to your wide receivers. Rico was better at getting open than some of the others in the room, but he still had his own significant issues with separation and getting open in one-on-one coverage against good teams. I suspect he can work on that and improve. If he leaves, the greatest impact will be short-term as it relates to the upcoming bowl game, as ND simply does not have enough bodies at the position right now. But I am not sure he walks into any top 10 college football program next year as the undisputed WR1 or WR2.
Edit: Rico announced his decision to transfer. Best of luck.