There is a hierarchy for the reading functions at the Liturgy of the Word:
49. Liturgical tradition assigns responsibility for the biblical readings in the celebration of Mass to ministers: to readers and the deacon. But when there is no deacon or no other priest present, the priest celebrant is to read the Gospel  and, when there is no reader present, all the readings. 50. It pertains to the deacon in the liturgy of the word at Mass to proclaim the Gospel, sometimes to give the homily, as occasion suggests, and to propose to the people the intentions of the prayer of the faithful. 
Does this mean that it is ideal for a non-presiding priest to read the gospel?
Also, handling the situation in which a lector is not present: rarely have I seen a priest do the readings. But it’s not unheard of. Is it better to have a decent proclamation by a lay person instead of the priest reading?
Note that it is the deacon’s task to “propose” (love that term!) the intentions. I’m not sure I see the benefit of that. Any liturgical scholar out there with the story on its history?
… or other comments?