I have not seen adjustable OCP on any PSU. They are designed for the model in question and they are unchangeable.
Corsair Link can set fan speeds and change the PSU from multi rail to single rail. That is all you will be able to do.
The PSU is not some glamor device, it has to run the entire machine, which is why I have a HX1000i to be safe.
The AXi and HXi and now the new AXi are all very efficient.
Now if only Corsair could provide some better 650W models, 80 plus platinum instead of the lower quality RM650x which is only 80 plus gold
The HXi series are great and I am pleased they are still available. The new AXi line are nice but slightly more expensive.