When exposed I only used them to tweak the variables, if at all. It’s a 99% C++ project, so I barely did any implementation of blueprint graphs in the entire project.
So you will find a bunch of Blueprints in the project, like the ClassicBomb which doesn’t have much blueprint logic (besides playing a sound on collision impact) but the Blueprint is necessary to assign content (mesh, FX, sounds)
Hope that helps,