One of the pipe makers (I forget who-Kurt Huhn?) noted that the ray pattern of a briar burl lends best itself to 2 shapes for a straight grain- the Dublin and the volcano/brandy. A good straight grain on any thing else depends on just the right block.
The blowfish is the one shape that, if done right, takes advantage of the briar block to emphasize straight grain and birdseye.
Having started pipe smoking in the 60s with the beautiful Danish pipes making their debut, I am a sucker for a straight grain.
docaitch