normal pitch on a 747 was 13 degrees 4 engine and 11for an engine inop. Cant remember a max as described above but I got twitchy as a fo if anyone hit 15 and I only ever saw that in the sim.
On a 737 the understood max is 20 because if you are reacting to a little shear with an increasing headwind then as soon as you pass through the shear the bunt forward is uncomfortable and unprofessional. The flight directors are set at 15 degrees for the takeoff roll until some seconds after takeoff and then targets v2 +15 tov2 +25 which works out around 15 degrees on two engines and 12 on one