The pen tool produces a slightly softened edge rather than a hard pixel-by-pixel cut, which reads much more naturally especially when compositing.

Rather than cutting directly into a mask, put the layer into a group and add a second mask to the group for any additional cropping. The original mask on the layer itself stays untouched.

Group the texture and set the group to a blending mode, not the layer itself.

This lets you add as many adjustment layers as you like whilst keeping the blending mode and texture layers unaffected.

Rather than using Overlay or Soft Light (which disappear on light backgrounds), use Linear Light or Hard Light for 'Paper Folds' textures, which work on light and dark areas equally. Then control the intensity with a Brightness and Contrast adjustment layer inside the same group.

Throw a 'Black & White' adjustment layer at the top of your stack to desaturate everything temporarily. If your colours are similar in value even if different in hue, the composition will read as flat. Forces you to assess contrast properly rather than being distracted by colour.