Servers should look good, or at least be thought of when considering progressive solemnity (more important feast = break out the nice albs or cintures or somthing! at least for those who will actually be on the Altar…). I like cassocks and suplices as much as the next guy but albs are generally the norm now, and though C and S looks better in general (when the servers have better albs than the infamous “bathrobes” I think they look just fine though) my particular bias is that clerical clothing be kept clerical or at least in that neighborhood. That is, though there are no longer minor orders, so they arent clerics precisely, I think it would still be acceptable for a seminarian (at least the Theologians) to use a C and S at masses and the like if they were in a role that was important (if they were funtioning as the Accolyte or MC for example, whether they were installed as an accolyte or not)
As to inspiring vocations, the clothes arent really the thing. I agree it is partially, though not entirely, the special feeling of being the one on the altar. I do have some particular biases regarding altar servers and function to maximize vocational discernment and that feeling of “specialness” which are inspired by a priest or two I respect deeply. But they definatly involve a co-ed system*, as that is what the Vatican has allowed. I cannot selectively listen to the Church. Yes, altar girls are an option now, and though option is the important word, the presence of that choice especially in America begs that that option be used, and rightly so.
*The system I am referring to is to allow the kids to serve regardless of sex and age, but they have roles that are not directly on the altar, and generally do not sit in the sactuary (crucifer, candle bearer, holding the book for the priest, carrying othger things in procession, ringing the bells at the concecration, etc). But the only server (or 2 on some occasions) that sits in the sanctuary (though out of sight or in a non-prominent place) and is on the altar directly and helps with the Lavabo or purification (purs the water, the priest of course actually does the washing), and puts the vessels and gifts on the altar, and incense, or any other work IN the sanctuary, is either a seminarian or a young man who is actively discerning. The “accolyte” group is a separate entity from the servers, and is generally by invitation or self-initiated request (no cattle calls). I like sthis system in many respects, though there are parts that I would change.
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