Several Big Matches Pitched For WrestleMania XXX, Possible Batista - Orton Change?

Source: F4WOnline
It appears WWE is strongly considering adding a third person to the Batista vs. Randy Orton match for the WWE World Heavyweight Title at WrestleMania XXX. The latest internal line-up says, "Batista vs. Orton vs. ?"
Other matches that have been pitched but not decided on include Big E vs. Dean Ambrose to unify the Intercontinental and United States Titles, Luke Harper & Erick Rowan vs. Seth Rollins & Roman Reigns, Sheamus vs. Christian, Cody Rhodes vs. Goldust and some kind of NXT match on the main card.