When people send me collections that include a couple of Roman coins (as is sometimes the case) I simply identify them and put them in a chronological order with the rest. I have mostly base metal coins now, and probably about 20 different emperors covered, including a few slightly unusual Roman ladies, and a Nero coin! No real direction, I just happen to be in a position that means I accumulate the odd one here and there. i do enjoy idenifying them, and learning about the usually brutal history of the folk on them.