***** NOT A TEACHER *****
I cannot answer your question, but I can pass along some information that may interest you.
1. A ball was in the street.
2. There was a ball in the street.
Two scholars claim the following:
a. "The first sentence could be one piece of information in a longer description where the writer is setting up the reader to expect something to happen."
b. "The second sentence may simply be a description without any accompanying expectation being aroused in the reader."
c. "[T]here is a tendency on the part of speakers to place given information at the beginning of a sentence and new information toward the end of the sentence."
Those two scholars are Mesdames Marianne Celce-Murcia and Diane Larsen-Freeman in their The Grammar Book / An ESL /EFL Teacher's Course. (I have the 1983 edition.)
Student or Learner