Improved CV inputs for VCO

As mentioned earlier, I'm not satisfied with how the VCO CVs work. Noise on the CV probably has a higher effect on the pitch than necessary. Here are my current thoughts on how to improve this:

First of all, move all summing resistors to the VCO board. This requires an additional pin for separate pitch and exponential FM input.

Second, reduce the Pitch CV resistor from 39k to 100k

Third, add a second pitch CV, also with 100k input, but make sure the CV is inverted (and 5V added to it) after it is generated. In this case, any noise present on Pitch CV 1, will be negated by the same noise on Pitch CV 2. Again, this requires an additional pin on the VCO board.

I'm pretty sure adding two extra pins here are possible, especially when removing the two resistors to the left of the top square (moving them to the VCO board).

 

The two 15p CV headers on the mainboard and the CV generation board can be replaced by 32 pin ones, like this female one:

https://jlcpcb.com/partdetail/XKBConnection-X6511FV_32C85D32/C2883749 

NB:

I am not sure how this is affected by noise on the ground plane, and how the VCO is affected by ground plane noise - because, if the noise is present at the ground plane (as seen by the VCO) but not on the CV generation board, the CV value will fluctuate, and vice versa. If it is present both places, I'd assume it would cancel out, but I'm really not sure about this.

Also, when adding 5V to Pitch CV 2, I need to think about how noise would affect this as well.