l can do 20 regular pushups and I've never tried to do more than one pyramid pushup--which is more progressive?

By pyramid l assume you mean triangle?
They target a different muscle group.
Regular = pectorals primary
triceps secondary
Diamond= triceps primary
pectorals secondary


If you can do 20 pushups in a row then you are in decent shape and definately can do more than 1 diamond.
Depending onwhat muscle you want to target, switch the pushups or keep them.