I've shown this project to two friends and each had a few ideas for future features. The first, whih I plan to implement immediately, is a dimmable LED flash. I already have the flash upgraded to LED, but it's only on or off. It's a standard LED taillight bulb for automotive use. 12 volts DC, probably about 1 amp current draw. I know that the GPIO pins on the Pi won't run that directly, so I found the Adafruit DRV8871 Motor Driver Breakout that should work nicely. My friend is an artist of many mediums, and immediately recommended dimming it for various lighting scenarios. I agree, so it shall be done. The flash module that mounts on top of the camera has 3 pins that it passes through. That's perfect for this. 1 will be 12 volts positive, another will be the ground, and the third will be the PWM signal. Couldn't have worked out any better than that. That PWM control should allow me to use the LED flash as a strobe light as well, which was another suggestion made to me.

Next is built in speakers for audio playback. I haven't looked at hardware for that, but it should be fairly simple. I'll be putting in an audio output for in ear monitors, and will just tie some powered speakers into that line. Will make gaming and video playback on the camcorder much easier, as I won't have to keep hooking up an external speaker.

A keyboard built into the lid that flips down to uncover the touchscreen. The space there is very limited, but I suspect I can get a grid of small momentary buttons mounted and use them for controlling functions outside of what the camcorder already has buttons for. I might even be able to fit an entire QWERTY keypad into it. Would make quick tasks much easier than plugging in or connection a keyboard. If I make that lid removeable and map the keys to main camera functions, it can be used as a hardwired control panel. That would help as the user wouldn't have to touch the camera in order to input commands, eliminating the chance of bumping the camera and shaking the image.

Along similar lines as the flip down keyboard, I'd like a built in LED light that would shine down on the keyboard. As much as I like backlights, I prefer the top mounted keyboard light on my Lenovo Thinkpad X230. Simple and very effective. I'll give the Pi control over that light so it can be turned off when the lid is closed, or when recording in low light situations where it might influence the image. 

Interior light. I'd really like a little interior light that turns on when the case is opened to make it easier to swap memory cards, cables, or just work inside of it. Simple, but would be very helpful if I ever had to work inside the camera under less than ideal lighting situations.

Autofocus. This is a big one that will require some extra hardware. The camera has the motor and hardware to implement autofocus, and it used to use it quite well. It uses an IR system, but I think I'll go with a simpler image processing technique. The only thing I need for that is a Python library for autofocus, which I already confirmed exists. Once I get the motor wired up and under Pi control, I'll start on that software.

Electric zoom control. THis camera also has a motor and hardware for the 24x optical zoon. I just have to give control of that motor to the Pi and map it to the original zoom buttons. Once this and autofocus are implemented, I can write programs to automatically zoom in and focus. This would be a great feature for when I don't have a camera operator and still need to zoom in and focus on a fixed point. Would be good for scripted work when I need the camera to zoom in on something I'm holding, then zoom back out after a set time. I've never heard of anything like this being implemented into a camera. I could make a fully automated studio where the host just follows the script and the camera does the rest. It's a large goal, but that's the end goal: single person automated recording studio built into a camera.

Pan and tilt motors. I plan to add Pi controlled pan and tilt on this, as soon as I decide on motors quiet and powerful enough to do it.  The Open Sentry project comes to mind. It may be a sentry turret system, but we can just replace the gun with the camera and use that system to track motion and colors and pan and tilt the camera automatically. It would follow the action as you walk around.

Time Lapse. I plan to program in a time lapse mode that can be adjusted as needed. I will do many ime lapse videos, and don't like how limited my GoPro Hero 7 Silver is in regards to time lapse functionality.

NAS. I'd like to have the secondary Pi act as a NAS that the main Pi will copy all video files to, so they can be offloaded from the camera wirelessly. Would just be a convenience feature for me, not really needed. I'm tired of copying files over USB and just want something easier, though it would be slower. 

Audio only recording. Sometimes I'll just need to record high quality audio for voice over work and such. I would like to start creating my own stock audio and video collection, and that would just be another convenient tool. 

Motion sensors. I was thinking about all the game cameras out there, and how much wonderful footage they get. That made me realize I could add in a motion sensor and use it like a security camera or game camera. I'd have to figure out how to turn the IR filter on and off for this sensor and I'm not sure that's possible. If so, I could also add a night mode and add an IR flood light to the camera. Low priority, but a fun idea.

Wireless audio interfaces. I want to have wireless lapel microphones for this camera, and will have to figure out how to interface those. The Pi doesn't ave any audio inputs, so you have to use USB or I2S interfaces. USB can have good quality, and I know there are some nice XLR to USB interfaces. I plan on getting one of those. I can also get wireless XLR adapters and just plgu an XLR lapel mic into one of those. I;m new to much of the camera world, but slowly learning. 

There are countless features I can add to this camera, and it gets overwhelming. I'll start with basics, like getting audio to work. I've borrowed a Zoom H1 audio recorder from a musician friend. It Records to SD, has a line out, and can act as a USB microphone. I can't get it to work as a USB mic, and I suspect the USB cable is power only and no data transfer. I made sure the firmware version is 2.0 or higher(2.10), but it still doesn't work. I'll return to this later. 

I'm done working on this tonight. Tomorrow is a new day(I need the power supply to charge my phone).