It's a brisket, right? So maybe a slow cook in the oven like a regular brisket would give the corned beef a little added flavor?
The good news it that it did have a marvelous flavor. The bad news is that it came out like a big hunk of beef jerky, impossible to slice.
So don't try to improve on perfection. Put the corned beef in the water, don't let it boil, and enjoy your St. Paddy's Day!