TL;DR; Allow each Project started to receive individual parameters.

I started out thinking this was a bug/omission in the existing "Parameters from properties file" option, but I now believe this should be a separate properties option: "Individual project parameters from properties file"

It's close to the functionality of the "Parameters from properties file" option, but with a critical difference: Each project specified in the "Projects to build", receive individual parameters.

A pictures explains it better:

All other functionality from the "Parameters from properties file" are still useful, and should remain.

Also note that it's not smart to add it as an option to the "Parameters from properties file" option, as it may still be needed to supply some common parameters to all projects.