Although I empathize with this patients frustration and their hopeful and optimistic search for some solution to the problem, in attempting to answer this question specifically to them, I would be entering into a doctor-patient relationship without having had the opportunity of meeting the patient or examining the eye. This puts me at a distinct disadvantage as well as to some medicolegal risk. If you are reading this because I responded to your inquiry and directed you here, please do not be offended by any lack of personal attention to your important questions. You will more likely learn more from this more extensive post then you would from a brief e-mail reply.
The following, in no particular order of organization or importance, are some important ideas, observations, and answers to your questions about floaters in younger patients. They will hopefully answer your questions as well as the questions you have not yet thought of.