There are versions of phones with waterproof battery compartments and certainly they could maintain their ability to control waterproofing the product of they still redesigned the access to the back cover via a more robust removable rear cover with gasket.
But with rear main cover more secure with screws possibly?
I'm not going to spell out how to tell them to make their phones, but maybe they might consider how users want to have the ability to change the battery themselves, and maintain the control of the device without sending it to a repair site for some time period.
Think of all the professional customers, besides all the soccer moms, students and retirees who they might dismiss right away.
Military & Government Officials, maybe even Senior Company Executives and tech companies that use these for everything from email and texting to secure encrypted NSA stuff.
Make it so they can be field repaired with a fresh battery seems like a no brainer?
That's my 2 cents!