I wrote about the words of hymns. Now about the music:

Why do we feel the need to imitate worldly music in church? Even if this were to be a good thing (and there is no reason why it should be) we do it so badly. The much loved Eagles’ Wings sounds like a bad Barry Manilow number. The other trite stuff is written in a pastiche style which imitates Broadway or Bob Dylan or Joan Baez. 
Many of the worship songs were written as either arranged choral numbers or ballads to be sung by a soloist with a guitar. ‘Make Me a Channel of Your Peace” is a perfectly nice ballad sung by a hip folk singer with a guitar, but the rhythms and phrasing are pretty much impossible to be sung by a congregation.
The music for a hymn is a unique art form in itself. A good hymn tune could be nothing else but a good hymn tune. It is written by an expert for congregational singing. Much contemporary Catholic music could be (with changed words) an advertising ditty, a folk song from Sesame Street or a tune from a third rate musical show.
A good hymn has a thumping rhythm and a simple, but memorable tune. It can be sung happily by the simplest of people. “Now Thank We All our God, With Hearts and Hands and Voices.” Now there’s a hymn that works.
Arguments against such hymns: 1) “It’s old.” This is a red herring. ‘Old’ or ‘New’ is irrelevant. We should ask instead whether it is good or bad. The only thing necessarily good about an ‘old’ hymn is that it is more likely to have stood the test of time. 2) The young people don’t like it. Another little red fish. Age has nothing to do with it. Some young people like new hymns and some don’t. Some old people like new hymns and some don’t. Some young people like old hymns and some old people like old hymns. What the young don’t want (in my experience) is being patronized and told that new hymns are ‘for them’. They especially cringe when they go to Mass and the only ones singing the ‘new hymns’ which are ‘for the young’ are their parents and other plump middle aged folks. 3) the words are too hard for the young to understand. According to this argument we should scrap Chaucer and Shakespeare and give the kids comic book versions of the classics. Forget Algebra and Calculus. Let’s keep them adding apples and subtracting the candy that Billy gave to Johnny. 4) These old hymns are Anglican or Methodist. Another red herring. So what if they come from another tradition? Evaluate them according to whether they are good or bad not who wrote them, but if this did matter has anyone stopped to check the denominational pedigree of Marty Haugen? Liberal Lutheran. What about the much loved Amazing Grace? Methodist. How Great Thou Art? Baptist.