I would agree that the Tuna Fish monologue from LAUGHING WILD is overdone, and I would stay away from it, unless you are amazing at it.
To be honestly, unless you are auditioning for a prestigious, hard-to-get-into theatre program, most directors will forgive slightly "overdone" material. They understand that you are auditioning for college, not a conservatory or a professional audition.
If you find something that you like and that you are exceptional at, concentrate less on how overdone it is and more on if you can knock it out of the ball park.
Something like Laura's MENAGERIE monologue or the monologue from THE SEAGULL are indeed overdone - but if you're good at it - they will recognize your talent and look forward to introducing you to new material and look forward to seeing you broaden your theatrical horizons.
You are a student, and if accepted, will be a student with them for the next for years. They're not expecting you to come in with someone they have never heard before - they're just hoping you'll be good, regardless of your material.
Best of luck.
"If you are going to do something, do it well. And leave something witchy."
-Charlie Manson