“do you have any other alternatives? “
There are sources within our mesorah that took an allegorical approach to Bereshit. There is nothing in our mesorah that would preclude HaShem from setting up evolutionary biology.
“I think that 5,771 years ago Hashem created the physical universe by rapidly expanding the initial singularity. Then at some point He said ‘dai’ and that expansion slowed to a crawl.”
You can think that, but there is no Tanna, Amora, Gaon, or Rishon who suggested it. The idea of a young universe looking old originiated with Christians in the 19th century. I get my hashkafah from Chazal and Rishonim, not modern Christians.
“I heard scientists claim there was no flood.”
There is absolutely no evidence that Mount Everest was ever under water, so this is a problem if you are a biblical literalist like some Christians. But Chazal say that the flood did not cover the entire world, so this is not a problem for us. Furthermore, there are flood narratives from different cultures all over the world that had no contact each other until modern times. Finally, there is absolutely overwhelming scientific evidence that sea levels worldwide rose by hundreds of feet about 11,000 years ago, and some evidence of other significant rises in bodies of water such as the Black Sea.
“Splitting the sea is not a rational occurance. “
Why not? There are places in Canada where tides regularly retreat 17 meters — vertically! Why could something like that not have happened at the sea at the time described in Sefer Shemot?