I don't know if you could modify a saito to do this. When you say less mess what are you referring to. I can't tell a difference between the oil from the vent versus the oil from the exhaust. It's a mess either way. I doubt you would even notice the difference in oil residue with this modification (in regards to a mess on the plane).

IMO this would be a waste of time, unless there are other benefits to this system that I am unaware of.