Clearly the Collect is intended for use in the most formal of settings. That does not mean that the formal Collects in prayer books can't be used as models for less formal times of prayer.
In the introduction to his Are You Running with Me, Jesus? Episcopal priest Malcolm Boyd mentioned a man whose son had died. His distress and agony were compounded when he wanted to pray and "did not know the words of a single prayer."
--This also was my experience when our son died in a car accident, not that long ago. It becomes very difficult for anyone to know what to say, or think, or pray. It is also very easy for individuals or families to fall completely apart. It is really a very deep distress that tears at the fabric of everything.
Then we found that we did very well to keep to our devotional schedule and at the time the Treasury of Daily Prayer was issued by Concordia Publishing House, in which are found many beautiful prayers and excerpts of books and sermons, together with the Bible readings. Onto this we hung what remained of our lives.
All the Collects in The Book of Common Prayer are ancient prayers, and I have copied the modernized version. It's still more formal than anybody ever speaks conversationally, and I would never attempt to ape that style in my own prayers.
Besides being easy to remember, though, the chief virtue of the form is that it forces me to place whatever I ask for in the context of God's grace rather than my own desires. If fact, if I cannot express a desire in the form of a Collect, I have to suspect that I need to meditate very specifically on how "not my will but yours" applies to the issue. In that way, what first seemed like a good way to structure public prayers became a means of evaluating to what extent my own desires.
--This is an important thought. Our own desires are not the primary thing in our prayers. They belong there, no doubt, but they are not primary. This is the only way to live with faith and hope in the light of tragedy. Even with joy.
The author suggests writing your own collects and gives an example. This would be an interesting exercise.