Just a couple of observations on the topic:
1.) A commentor on an Orthodox blog once responded to the cassock vs. collar question. He/she made the point that in many cases, converts to Orthodoxy are opposed to the collar, while many clergy from the Middle East are opposed to the cassock. Why? Because some (albeit not all) converts are coming from the "dreaded West" and wish to shed all vestiges of where they came from, while the Middle-Eastern clergy in this country sometimes view the long robes and beards as reminders of Islam, and thus feel more comfortable wearing the collar.
2.) When it comes down to it, a priest needs to be obedient to his bishop regarding clergy dress. If anyone else has an issue with what a priest is wearing, unless he is that priest's bishop, that person may want to consider that it is he, and not the priest, that has the real problem.