One thing I'd like to mention,
what you're going to do will also depend largely on how the round house is being thrown. If it's a "load from the hip" that you often seen thrown in Kyokushin, or a chamber from the knee, then stepping forward etc will work just fine.
Not to mention that any kind of the afore mentioned kicks will leave you in a precarious position if you're caught in the middle of it (like someone previously noted)
You'll want to be careful if its a person that throws it orthodox thai style. Simply "catching" or "crowding" might not be so simple since they keep their "axis"/spine relateively straight and don't break that alignment as much compared to the methedologies I mentioned earlier. This allows them to keep their balance even after the kick is "caught", or if they're crowded, which could end up in the would be "counterer" eating an elbow in the face
Really the only way to find out is experiement though.
Think less about technique, and adherence to principal
From my experience, maintaining the bodies aligment,or dynamic balance, "kokyu chikara" whatever you want to call it, and maintaining at all points through whatever technique you choose is the critical factor you'll want to focus on.