Your questions have already been answered but it seems you fail to understand them because you retain erroneous preconceptions. So once more unto the breach...
1. A common interface is used for both the Japanese and Allied player. However because the Japanese player can modify his production, his interface allows for more tinkering. Read chapter 13 of the manual which goes into detail and the “Interface Addendum – v1094b” found in the “Manuals” subdirectory. When reading the latter continue repeating to yourself – only Japan modifies production, Allies enable production only.
2. The Australian Wirraway light bomber does upgrade. You are simply not looking in the right place to see the upgrade path. Click on the Information Button (short key “I”) then click on aircraft replacements. All aircraft upgrade paths are listed on the extreme right hand column. For the Wirraway, it upgrades to the Boomerang C-12 which enters production in February 1943.
3. Allied on map “industrial” production facilities can be classified into three categories:
(a) raw material production – (resources and oil)
(b) consumer goods production – (both heavy and light industry, plus refineries)
(c) elaborately transformed manufactures – (aircraft factories, repair shipyards)
In all three categories, the Allied player can not, repeat again, can not modify his production. An Allied player is limited to enabling his “industry” to produce. Hence an Allied player can determine whether to:
(i) allow his damaged industry to be repaired (applies to all three categories) – this will consume supply
(ii) allow his on map elaborately transformed manufactures (aircraft factories only) to auto upgrade to the next aircraft model on the scheduled predetermined upgrade path or remain producing the older superseded model
(iii) ensure his on map consumer production facilities have the necessary raw material feedstock to enable the production of the consumer goods.
4. To see how paragraph 3 above operates in practice, look at Pearl Harbor. Pearl Harbor has 1 raw material production facility (resources), 2 consumer goods production facilities (heavy industry and light industry), and 1 elaborately transformed manufacture facility (repair shipyard). If any of the three categories of “industrial” facilities is damaged, you can repair them at the cost of expending local supply. For the consumer goods production facilities to produce their consumer goods they need to have their raw material feedstocks (resources and fuel to feed the heavy industry, resources to feed the light industry) present locally. Pearl Harbor has no refinery production at all to produce fuel and its local resource production is insufficient to fully feed its two consumer goods production facilities. Accordingly you must import both fuel and resources.