A lot will come down to how the part will be produced.
Connecting rods are likely cast, then machined. Or simply machined from stock.
Optimizing a connecting rod would likely lead to the need to create it via 3D printing, which is going to be more expensive to produce.
Other factors to consider are the trade offs in saving weight in a component like a connecting rod. Like a flywheel, a lighter connecting rod may allow for quicker acceleration, but it would also loose momentum quickly.
Regarding strength, I feel that optimized/organic parts can be stronger than their billet counterparts, but it really depends on the ability to capture all loads which will be seen by the part. Connecting rods are a pretty good example since they are largely a reciprocating component.
If money were not a limiting factor, and making a lightweight engine were the top priority, this might work out well.
I wonder if optimized parts shrink and swell at the same rate as solid cast or billet parts?