Here's some easy options to starting phasing in to save us all time!
MyDisneyExperience app users should be able to take a selfie and link it to their ticket through the app. Once linked, it can only be changed by Guest Services. This solves a majority of issues, provides photos for everyone to CMs, and prevents guests from changing the image and robbing Disney of their precious over rated ticket prices. If I can depost checks to my bank using photos from my phone taken at home, I should be able to knock this issue out to streamline my vacation.
The same app, when used with iPhone 6 & 6Plus should allow users to pre-calculate their finger print signature and link that as well. Using the same process as at the gate, but performed on the iPhone before arriving, will again speed access and leverage technology in your pocket.
Another option would be to use register the iPhone the app is on with your MyDisneyExperience bands. If an issue ever arises, "tap to pay" without paying. This would simply match the ID of the device with the wristband being scanned.
Done and done. You're welcome for the simple solution Disney. Now just let us in so we can take advantage of these great new prices!