I know of at least one priest who is naturally a good speaker. And I was a Protestant for 17 years and there is definitely more of an emphasis on a good sermon in Protestantism because if you can’t preach well, people usually aren’t going to keep coming to your church. Of course, that doesn’t mean there was much of tremendous substance there either, just that perhaps the stories were interesting or there was some humor.
What I usually look for is substance, to learn something. Thus I think the emphasis should definitely swing back the other way to preaching on Catholic doctrine. Obviously, there is a wealth there on any number of subjects one can preach on. Further, I don’t think one would have to be a really good speaker to get something across of genuine value, and Catholics would be learning about their Faith at the same time.
I think the gospels are actually better as something to think about and meditate on in preparation for Holy Communion. And unless one is Bishop Fulton J. Sheen often there really is not much in a homily based on the gospels that is of real value.
Also, in Protestantism, the minister usually gets to preach on whatever scriptures he wants to,–whatever happens to catch his fancy. Priests don’t have that “advantage.”
I simply don’t think Priests should be restricted to preaching on the gospels, or having to tie in their homily to the gospels. If they want to, great, but I think they should have full leeway if they want to, say, preach on sanctifying grace, or purgatory, to do so (actually I think preaching Catholic doctrine should be the first priority), even if they aren’t able to tie it in to the gospel readings for that day. The gospels can stand on their own.