Several countries modified the E to carry the Python3 on the outboard pylons. Normally not used together with the AIM-9. Some sort of helmet mounted system too, but was not a Northrop mod. I do not remember seeing the E with 4xAIM-9. Would be a pig for dogfighting with 4xAAM too.
Fuel probe, several export customers had it. Was asked for before, IIRC official response was "thinking about it but will be difficult". Data exists, it might be that the work is too much for the project to be considered financially viable. My #1 request for the F-5 though.