Nadine
I think you may find the 727 settings were 30 and 40 as the 737. 30 was the norm for many operators due to minor buffet with 40, not considered good
PR. 15 degrees used for most non-normals. Experts please correct if necessary.
The 1-11 400 and 500s normally landed with 45 degrees, 26 used for engine out.
26 would also be used for landing when WAT (weight for altitude and temperature) limited and engine out is then 20 degrees. Total hydraulic failure and stuck tailplane also 20 degrees.
Landing distance for 26 and 45 flap is the same, withe pilot required to observe Vref Max of +10 kn with 26 while it the normal +15 with 45.