I did a wedding cake tasting at Two Little Red Hens, and yellow cake (vanilla butter cake) with vanilla buttercream was part of the tasting. I thought it was very good, great vanilla flavor, moist, etc. I would give them a try.
I had the most fragrant and delicious warm vanilla cake at a restaurant a few years back, but I can't remember the name of the place for my life's sake. It was in Midtown somewhere. If I remember I'll come back to the thread. If you like vanilla cake, you'd LOVE that one.