It would be convinient to have a Bypass toggle for each block in MathMix and MathCombine POPs. I often find myself removing an enitre block or wanting to just try out a different operation on values and the current UI only allows you to either delete or modify the block. I find with really complex systems you could have a lot of operations in a single MathMix or MathCombine POP and it might be helpful for debugging and provide better visibility into how each operation affects the output.
In terms of UI it would be great to have toggle on the parameters itself or the RMB menu in case it makes the parameters UI more cumbersome.