Tim I also have a 46 mile (exactly) commute.
It sounds like you are already doing some things, but I'll say for me to get my own numbers requires a pretty radical departure from the "norm".

I'm heading into Atlanta while everyone is heading out, so I miss the terrible miles upon miles of gridlock traffic, and usually park at about 68-73MPG.
I leave work again in the wee hours of the night on nearly abandoned streets and have the opportunity so I really work it as extreme as safely and practical as possible. I usually park with 70-76 on the dash.

If you'd like a play-by-play I'd be happy to pound one out for you how I do it but would likely be a very long post.

Efficient drivers do it better.
1003 miles a tank personal record. 74MPG calculated. HCH1 CVT