Making Greco eco at the highest level higher scoring seems very hard to do. The down side of going for a throw and missing is so severe and missed throws become more and more likely against opponents with world class defense.
Can you expand the slipped throw category so that you can only score off an offensive maneuver?

Some throws- arm throws, headlocks, ect- are pretty safe (as in, you won't pin yourself screwing them up). IF the slip-throw rule was changed to to the old rules, where people were stood up after a slipped throw (no parre terre) you will likely see more of those.

I don't think greco on the feet will ever become super high scoring; it's just too easy to defend most upper body attacks. (Incedentally, that's why I enjoyed wrestling the odd greco tournament long after retiring from freestyle- easy to stall and catch your breath). Wha'ts important is that the rules adequately encourage the spectacular moves from par terre. Right now they don't- most guys will either to a gutwrench or a one point lift to the out of bounds- not much risk and a 1-0 period win is just as good as a 5-0 period win.