If "calls and requests" is your problem then, as far as I can see, the XML does not seem to be the problem. The XML is only the container around the data you want to send and receive.
You will need to give some more information to have any chance of getting help.
A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James
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