I believe that parents and good priests foster good vocations to the priesthood. But it is bad theology to say that the priesthood is a higher calling. This kind of thinking has lowered the sacred institution of marriage. There are some parishes I know that will pray for VOCATIONS to the priesthood, but refuse to call bans of marriage a VOCATION. Clericalism was born of this type of thinking. Sorry, but I don't buy it!
PS: I reverence the priesthood with all due respect and love. But I can't believe for one minute, knowing that vocations are gifts and individual callings from God, that He would short change any other vocation He called a person to.
I can't imagine any life of celibacy being more of a source of growth than the life of a spouse and parent. I don't really think the average parish priest has a "more" difficult life....difficult in a different way, but not tremendously difficult.