Over shabbos, I locked myself away with Moshe Dovid Cassuto's From Adam to Noah: A Commentary on the Book of Genesis, I-VI. Cassuto, of course, was an Orthodox Rabbi who was able to combine loyalty to the mesorah with a willingness to follow the evidence.
In particular, he argues (quite convincingly) that the story the Torah tells about Noah is an homogeneous whole, and not two competing stories that were knitted together. His evidence for this includes the fidelity of the Torah's story to fragments found in Mesopotamia, and also the fact that many key words appear in the story 7 times (or multiples of 7.) Though Cassuto does theorize that the Torah's story is based on an older epic poem (this explains the use of strange words like Tzohar and Kinim) this theory isn't a challange to the idea of divine revelation. We all agree that God used words and ideas that were previously known to the people. Why couldn't He have also drawn on pre-existing themes or poems?
Best of all, Cassuto points to evidence in the text that suggests Noah's flood was a regional flood, by which we mean one that affected Mesopotamia, and not other parts of the globe.
This opinion is appealing because it preserves Noah, and the mesorah, without insulting our intelligence. If we hold that the flood was regional, the absence of geological evidence of a flood in places like China or Europe is no longer troubling. (The theory is further bolstered by the presence of flood evidence in Mesopotamia.) Nor must we explain, if we follow Cassuto, how all the races of the world descended from the 8 people who were on-board Noah's ark. Per Cassuto, most of the world was unaffected.