Could guards be a different from one and other

In skyrim all the guards had exactly the same stuff and the only thing different was the armour deppending on what hold they were. Could you make it so they have different roles like they could be a commander and then like a captain or something to make each guard unique.because its a bit boring having to see the same guards how look exactly the same, talk exactly the same and say phrases exactly the same. so could maybe guards have a different voice not all of them but some of them. And maybe you could have different races being guards rather then just nords.