Today, I shall attempt to show the world how the various options for Bethel and Ai might work. Sadly, I only have time to do Option 1:
Bethel=Beitin, 31°55’36″N, 35°14’20″E
Ai=et-Tell, 31°55’0″N, 35°15’41″E
Iron II B-C Ai (if Nehimiah 7:32 and/or Isaiah 10:28 refers to this Ai)=Deir Dibwan
Hellenistic Ai (Nehemiah 11:31 is referring to Hellenistic data, as Beitin was uninhabited in Persian times)=Khirbet Haiyan, 31°54’18″N, 35°16’17″E
Mountain of Gen 12:8=Burj Beitin (Byzantine-Crusader remains only), 31°55’21″N, 35°14’42.18″E
Valley to the North of Ai: Wadi el-Gayeh. At present, it would be hard to see anything in the valley, but et-Tell certainly had watchtowers.
Ambush site between Bethel and Ai not visible from Ai (Bethel does not matter, see vs. 17): Anywhere on the western half of the ridge between Burj Beitin and et-Tell would be okay if the walls were under 100 ft. high. While the narrow part of the valley at 31°55’36″N, 35°15’25.20″E could have provided some cover, the western option remains preferable (Josh 8:9).
So, the scenario works, except for the fact there is no suitable candidate for Beth-Aven, Josh 10:2 is dismissed (et-Tell=27 acres, Gibeon=16), and the mountain of Genesis 12:8 is turned into a low ridge.