Ed, more drops or jumpers can't hurt. But you never told me whether you put a 6" level along the right-of-way in the suspect areas, as I suggested.
Series motors like the Pullmor are very sensitive to changes in load. Even a slight grade will cause them to slow down. If your benchwork was built a while ago, the surface might have sagged between supports. Homasote or ceiling tile used for the layout surface can absorb moisture and swell. This is a difficult problem to solve! If the layout was bumped or moved, perhaps it needs to be shimmed again.
Put a short level on the track, about the length of the loco's rigid wheelbase. Move it along the track a little at a time in the direction of travel, and look for any bumps or rises. Although they have less "personality," the can motors in today's locos are less affected by this type of undulation, even without cruise control.
