I did a search for this topic, and I coud not find anything useful. As many time before, inkscape was the answer!
if the EPS file is vectorial, (could be generated with MATLAB for example), it turns out that it can be edited as a regular file in inkscape, you could change colors, fill and stroke properties, fonts, etc, you could even add LaTeX formulas if you have the tex text add-on installed. Awesome!