It depends on the number of tobaccos. A simple English blend of three tobaccos -- for example Virginia, Lat, and Turkish -- goes well in any Group 4 (medium sized) billiard, bulldog, Dublin, etc. For blends with four or more tobaccos (number arbitrary but maybe useful), I like a wider bowl as is often typical of a pot, prince, author, diplomat, etc. I somewhat accept the theory that a wider bowl gets more different leaf going at once and gives a better range to the blend. Of course, this is all subject to trial and error, and sometimes a pipe that shouldn't work is ideal. For burley single leaf and burley blends, I often like a standard width chamber this is deep, like a Hungarian, a cob freehand or General, anything with depth.