Obviously CI are very expensive (some/most insurance will cover) and require hospitalization and surgery to implant. Getting a CI also means that person can no longer have MRI scans performed unless the MRI machine is below a certain magnetic threshold or the magnet on the implant is surgically removed--though I am told the latter can be done outpatient.
Researchers are working with a prototype of a new type of "hearing aid" that is "implanted" in the ear drum, a very minor surgery that is done outpatient. The implant can reach 120 dB, which is fairly amazing. More details on this link: