I developed a system, and wrote a paper about it. It includes formulas and pseudo-code. During the course of development I used Roman letters in the formulas. I eventually ran out of meaningful letters (letters that I could associate to some extent with what they represented), and started using Greek letters. The development went on until somehow I ended up having about 8 Greek letters and 2 Roman letters used in the final formulas and pseudo-code.
Now that the paper is written, I wonder if having all of these Greek letters is unusual. Would it be better to replace them with Roman letters? Would it be better to use Roman letters with subscripts, such as t for time, and t_scaled for scaled time, instead of using Greek letters for that?
EDIT: To clear things up a little, my general question is: is it preferable to use Roman letters or Greek letters in a technical (engineering) publication, and is it acceptable or even preferable to use letters with word subscripts instead of entirely new symbols to label related variables or constants?