anybody is free to write a book of prayers about any topic, and they (like hymns) would be fine as long as they did not contradict Catholic doctrine (i.e. praying to God our Mother). Such prayer books or devotional aids may or may not be helpful to some people.
The Liturgy of the Hours is the public prayer of the Catholic Church, as is the Mass, and nobody but the Church has any right for (name removed by moderator)ut, or the write to re-write the prayers and readings, or to change the order and times required for those who have the duty, by virtue of their ordination or religious profession, of praying the Divine Office. (Religious orders of course are free to make their own adaptations, without of course re-writing the actual scriptural portions of the prayer).
The Holy Spirit inspired the writers of the psalms, canticles and readings that comprise the LOTH, so no mere mortal working unaided is going to come up with anything better.
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