The power to bind and loose was given to Peter in Matt 16 in a way that it was not given to the other Apostles in Matt 18. The evidence of that is:
1) the turning over of the keys, which only occurs with Peter
2) the name change, which only occurs with Peter
and 3) the fact that Peter is given the power to bind and loose singly while the others are given it corporately. In Matt 16..it's the singular, referring only to Peter. In Matt 18, it's in the plural. "whatever you all bind on earth will be bound in heaven". The power that all the Apostles have seems to be somehow "crystallized" in Peter in a way that it is not with Andrew, say, or John or James.
Also, I don't think devolving Peter's power to the Apostles helps you any, if you don't think that there is any authority in the Church save Christ alone. Matt 18 practically screams ecclesiastical authority...not only in the Apostolic college having the power to legislate, but also the power to excommunicate in Matt 18:17.
Binding and loosing...whether through Peter singly or the Apostles corporately..implies legislative authority over the Church. This is something that not every believer can have.
Saul took the name Paul, and in Acts we see another name change,
Acts 4:36
Thus Joseph, also named by the apostles Barnabas (which is translated "son of encouragement"), a Levite, a Cypriot by birth, sold a piece of property that he owned, then brought the money and put it at the feet of the apostles.
Levi was renamed Matthew, Jesus renamed James and John, Boanerges, Nathaneal is renamed Bartholomew.
Jesus renames all of us
Re 2:17 He that hath an ear, let him hear what the Spirit saith unto the churches; To him that overcometh will I give to eat of the hidden manna, and will give him a white stone, and in the stone a new name written, which no man knoweth saving he that receiveth it.
Binding and loosing and the priesthood of all believers . . . as Paul makes plenty clear . . . is given to all believers.