I've started looking into 3-D designed musical instruments (yes that's apparently a thing now) and wanted to know if it's a good direction, if I want to customize my own electric guitar
The critical parts of the guitar for sustain and tone are all between the nut and the bridge, so if you add any shaped pieces on anywhere else they will not make audible differences.
On the very high end guitars, the "horns" and other bits are designed to resonate at specific frequencies so they will have an effect on sound, but for most guitars any effect from these is not going to be audible over the impact of wood or glue choice, electrics, pickups etc.
For some of the electric guitars I have made I have changed the shape over time by hacksawing off various bits; making sure I didn't touch that critical core. There was no change I could hear.