The Biblical commandment of prayer is worded as an enjoinder to serve G‑d with "all our hearts"--which the Sages understood to be a commandment to pray. Originally, everyone offered personalized prayers, employing words which expressed their unique feelings. And as feelings fluctuate, so did every individual's personal prayers fluctuate on a daily basis. Eventually, the Men of the Great Assembly instituted uniform prayer for all Jews, creating the basic text of the prayer book which is used to this very day.
But can a person's relationship with his Creator be scripted? Is it possible to dictate the feelings one should be expressing to G‑d?
We live in a world largely obsessed with external trappings. Everything is judged by its most revealed dimension, while the essence goes unnoticed. Uniqueness is expressed through a nose-ring or sports car, not through emphasizing character and wisdom. Sometimes it is necessary to have two items which are externally alike in order to appreciate the profound difference which actually exists between the two.
The challenge we have is to create a personal prayer filled with personal feelings and sentiments — while using the same words as the person sitting next to us in the synagogue. This means truly immersing oneself in the prayer, for if the vessels are empty, if the words lack a backing of feelings and concentration, then the prayer which is being offered is actually no different than the prayer of every other John Doe.
And G‑d loves unique prayers…

I love everything you've written and I also love the comments on it. Kol Hakavod. For me, prayer has saved my life. In my childhood as my family and world raged around me prayer was the lifeline Heavenward. Years later I was blessed to discover the siddur. It didn't take the place of my own spontaneous prayers but it did add a new dimension of connection: the silence of connection. As I say the words of the siddur I'm no longer speaking: I am the means for the words to be articulated and sung but my ego is out of the equation. The words that emerge from my mouth and course through my consciousness are the words of the Jewish people throughout the ages where they stuck to their ideals no matter waht. Sure I have my own yearnings (I'd like to lose 40 pounds and have a couple of million in my bank account among other things) but as I say those words I'm no longer me: I am a Jew, I am the creature who stood tall and who stood smart before this world.