Hey @GarfieldModular, thanks for your comments. I agree (and it's on my plans) to have more than one VCO, not sure if a Dixie. My fault it's not there.
A second Filter wasn't planned but I will consider with care. I really look for a Filter that could give me more than just Low Pass Gates or Distortion, something that I could modulate and use as a sound source if necessary. Suggestions are more than welcome.
Regarding the AD or ADSR,I consider also the Doepfer A-140-2 as an option, it's also way cheaper than Intellijel Quadra.
The case can't be too big at the moment 9u would be wonderful but I don't want to scare my wife with my sonic ambitions, I will wait for her to get used to my little box before anything bigger land in the room!
Thanks and take care!