Very interesting, I'm sure one of the drilling patterns common to other performance engines will be an improvement. Unfortunately it is tough to do testing with out actually spinning an engine fast enough to scuff the bearings to find out if you improved things much.
I would be very interested to see what sort of experience you see with those modifications.
I also favor the single entry style oil hole. The Subaru bearing is nearly a 360 oil design as it has a full oil groove behind the bearing shell in the mains, and feeds the oil through multiple oil holes so I'm not sure a true grooved shell would be necessary to benefit from the changes.
If I understand you correctly you appear to have created a "V" drill pattern with your modifications so the runner that carries oil from the main to the rod crank pin picks up the oil near the surface of the journal.