
To have or not to have?
In the briefing of the very first scenario, namely 1 Shanghai 1937, you've written: "Furthermore, all of our planes were shot down in the first month and a half of this battle, so the Japanese have complete air superiority."

It's annoying because it takes away a dimension from the fight (no pun intended - well, if a little

Let's make some readings, shall we?
First from https://en.wikipedia.org/wiki/Aerial_en ... panese_War :
" Battle of Shanghai/Nanjing [...] While seeking to better compete against the highly advanced Mitsubishi A5M fighters of the IJNAF, Colonel Kao Chih-hang on a morale-boosting shakedown of his men and performance-boosting of his machines, had his maintenance crews remove the bomb-racks, fuel tank cowlings, landing lights, etc., to save weight and reduce drag off the Hawks, and on 12 October 1937, he led an aggressive seek-and-destroy mission consisting of six Hawk IIIs, two Boeing P-26/281 "Peashooters", and a Fiat CR.32 in the opportunity to engage any approaching Japanese fighter aircraft. A group of Mitsubishi A5Ms soon appeared on approach to Nanking and Col. Kao led his group into a melee, where Maj. John Wong Pan-Yang, a Chinese-American volunteer pilot from Seattle flying one of two P-26 "Peashooters", drew first blood shooting down the A5M piloted by PO1c Mazazumi Ino. Capt. Liu Cuigang shot down another A5M that was sent crashing down into a "Mr. Yang's residence in southern Nanking", and Colonel Gao scored a double-kill against the A5Ms, including that of shotai leader WO Torakuma, all before jubilant spectators of the city of Nanking. This was a monumental moment of air-superiority exhibited by the Chinese pilots due to the great experience of Col. Gao, Maj. Wong and Capt. Liu in particular, as they were outnumbered and yet so convincingly defeated the Japanese fighter group flying the far-more advanced Mitsubishi A5M "Claudes".
Battle of Taiyuan
As the frontline battlefields raged at the Battle of Shanghai and Battle of Nanking, pressing demands for aerial support at the Battle of Taiyuan in the northern front and Canton in the southern front, forced the Chinese Air Force to split the 28th PS, 5th PG based at Jurong Airbase in the Nanking defense sector into two smaller squadrons, and then dispatching half of the squadron to the south in Guangdong under the command of Lt. Arthur Chin, and the other half to the north at Taiyuan under the command of Capt. Chan Kee-Wong. [...] "
Our scenario starts at the begining of November 1937. The first fights at Shanghai around mi-August 1937, so the fights are in their final part near Shanghai, that's right. More than 2 months and a half, roughly, of fightings before our scenario does start.
According to the previous text, at mid-october 1937 Chinese pilots were able to carry on flying and achieving great results. Moreover, during the Battle of Shanghai itself, parts of the Chinese planes have been sent for aerial support at two other sectors...
Now, when you write "Furthermore, all of our planes were shot down in the first month and a half of this battle, so the Japanese have complete air superiority.", then there is a little issue...

Sure enough, the Japs may have an important air superiority... but the Chinese are still flying proudly!

Let's carry on, shall we?
This time with some extract from here: https://en.wikipedia.org/wiki/Developme ... 80%931945)
" [...] Operations
During the Second Sino-Japanese War (1937–1945), which is often regarded as the beginning of World War II, the ROCAF participated in attacks on Japanese warships on the eastern front and along the Yangtze river and interdiction and close-air support during the Battle of Shanghai in 1937. Chinese sources estimated the Japanese could field approximately 600 aircraft (from a total of 1,530) against China's 230 combat-ready aircraft. As the Imperial Japanese Army Air Service and the Imperial Japanese Navy Air Service conducted mass-terror bombings against both civilian and military targets, the Chinese Air Force also planned raiding Japanese home island with the Martin B-10 bomber that was suited for the trans-oceanic raid.
The initial lineup of Chinese frontline fighter aircraft included but not limited to the Curtiss Hawk II, Hawk III, Boeing P-26C/Model 281, Fiat CR.32 among others. These engaged Japanese fighters, attack/bombers and reconnaissance aircraft in many major air battles beginning from 14 August 1937, when Imperial Japanese Navy's Kisarazu Air Group raided Jianqiao Airbase with the schnellbomber strategy, but suffering heavy losses; "814" has thus become known as "Air Force Day". Chinese Boeing P-26/281 fighters engaged Japanese Mitsubishi A5M fighters in the world's first dogfight between all-metal monoplane fighters. A long-distance "bombing raid" over Japan on 19 May 1938 saw two Chinese Martin B-10 bombers led by Captain Xu Huansheng fly into Japan, albeit dropping only anti-war leaflets over the Japanese cities of Nagasaki, Saga, Fukuoka, among others cities.
It was a war of attrition for the Chinese pilots, as many of their most experienced ace fighter pilots, such as Lieutenant Liu Tsui-kang, Colonel Kao Chih-hang, Yue Yiqin, among others, were lost; six months into the war, the Chinese Air Force inventory of frontline American Hawk IIs and IIIs and P-26Cs, and various others, were mostly superseded by faster and better armed Polikarpov I-15s and I-16s provided under the Sino-Soviet Treaty of 1937, including Soviet volunteer combat aviators. However, with the Fall of Nanking, the Fall of Wuhan, and the losses at the Battle of South Guangxi, the primary supply-line of China's "war of resistance" against the Imperial Japanese aggressions was dealt a further blow, not least of which the high-octane aviation fuel that was blocked-off from Chinese access, but still accessible to Imperial Japan.
After suffering heavy losses in the Battle of Wuhan in October 1938, most active air force units were withdrawn hinterland for the defense of Sichuan against the most brutal terror-bombing raids ever inflicted upon civilian populations up to that time; the massive Japanese carpet-bombing campaigns, against targets in Sichuan, under the codenames Operation 100 and 101, were also fiercely contested solely by the Chinese Air Force units and anti-aircraft artillery units, sometimes with significant Japanese losses. But as China was not an aviation-industrial power at the time, losses continued to mount, while the Japanese forces enjoyed a highly-developed aviation industry that saw constantly improving cutting-edge technological advancements giving Japanese aircraft distinct performance advantages in speed, agility, altitude/climbing rate and firepower that greatly placed the increasingly underpowered and underarmed Chinese fighter aircraft hampered with low-grade fuel at tremendous disadvantage. With the introduction of Mitsubishi A6M "Zero", the most advanced fighter aircraft of the time, the Imperial Japanese gained practically complete air-supremacy by 1941, giving the Japanese military high-command full confidence in proceeding with the implementation of Operation Z (the planning and rehearsals for the attack on Pearl Harbor). [...] "
By 1941 only the Japs have practically gained a complete air-supremacy... Only by 1941!
