Bundling existing H5P content into a Quiz

Is there any way already or at leaset a plan for adding the ability to bundle existing activities into a quiz (question set)? We are in the early stages of a project and I am not sure which way to go (quiz or separate activities). We won't run usablity tests until later and won't know if it is better to create separate activities and embed each one in the page and give the student the choice which ones they can complete, in which order or guide them linearly through a quiz. That's why it would be great to have the option to create activities and maybe add them later to a quiz.