I would recommend keeping the ability to use the USB-Serial adapter. At least for initial setup and firmware updates. I did do a firmware update over bluetooth but it takes longer and I am not sure what will happen if you loose connection in the middle of an update. I cannot imagine it would be good, so my firmware gets updated over USB.
Also, I don't think that bluetooth is fast enough to capture a trigger log, so having the ability to swap the USB-Serial adapter would be valuable, but maybe not absolutely necessary.
Jim