I did a quick search to see if anybody else had posted anything about it and I did not see one, so, I am sorry if this has already been suggested.
I would really like if there was a way to change the common Math functions, such as “Add”, “Subtract”, “Multiply”, “Divide”, etc.
I know there are shortcuts for those “CTRL + A” = Add, “CTRL + M” = Multiply; however my problem is that I have to re-assign each connection-line to to the from the one thing to another. And if you have a lot of them, it’s quite messy.
I don’t know how such things works but it would surely save a little time for a lot of people. Well, maybe.
For example, in my case, let’s say that I have an “Add” but I want to use an “Multiply”, then I have to delete the “Add” and wait for the “Compiling Shaders”, then I have to remember where the nodes were connected and then connect them, again, then wait for the “Compiling Shaders” to finish again.
I know it’s not a big issue or anything and that I could probably be less of a messy artist. 
Thank you for reading,
Lucas-san