With regards to the fuel gauge, it is a common issue, efi has nothing to do with it, just means the pick up in the sender to the gauge are worn or dirty, my car does the exact same thing.
As far as the surging, I would look at fuel pressure, check to make sure the fuel reg is working, and check your injectors, if they are dirty or blocked it will do exactly what you are describing, two pumps is over kill and one will not slow the other, unless they are running in line back to back and one is blocked.
The other thing worth checking is that you are getting a consistent fuel supply, ie it is not getting blocked at the pick up end by anything.
Good Luck
Jon