Maybe a triple width Shruthi w/the Polivoks and 4 Pole on either side w/the main system in the middle. Extra boards could be underneath the main and both side boards. Add controls to allow for switchable filters, maybe CV as well. Of course, w/the Polivocks, 4 Pole and main kit all included, you would have a 3 voice Shruthi w/a lot of filtering possibilities.
Just an idea. I have no electronics skill, so this would be a down the line, get my friend who is good at this kinda c**p kinda plan

Both boards:
4 Pole Mission Shruthi 1 35 Euro
Polivoks Shruthi 1 35 Euro
Filter board and chips:
Shruthi 1 Digital FIlter PCB 40 Euro
Shruthi 1 Dual SVF PCB 25 Euro
Filter board only:
Shruthi 1 SSM2044 15 Euro
Shruthi 1 CEM3379 VCF/VCA 15 Euro
Control board only:
Shruthi 1 Digital/Control PCB 15 Euro
Chips:
Programmed Chips 15 Euro