I am thinking about just making my own white balance options that can be applied to any camera. I am having a tough time justifying putting much more investment in the indi_rpicam driver. It is becoming increasingly apparent that it may be a dead end.
Arm64 is set to become the de facto architecture for ARM SoCs and the library used to communicate with the Raspi HQ camera (MMAL) is not compatible with arm64. The Raspberry Pi folks are working on replacement libraries, but INDI support is based on MMAL, so INDI is probably starting from scratch if someone wants to try to support the libcamera library.
Maybe I am wrong (I hope I am wrong) but the outlook is not so good.