Just to add a few things:
Naval Bombers and Carrier Air Groups are equally good at doing Strategic Bombing, better than anything else except strategic bombers (mainly due the need for strategic attack for port bombing).
CAS is better known as 'dive bomber' (it approaches the target in a big altitude, once above the target, it's supposed to dive vertically, while the pilot tries to bring the target in his sight - once done he releases the bomb and turn up again).
Multi-Role (at least in WW2) are just normal fighters (Interceptors ingame) with attached bombs.
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If you focus on the RAF as UK, it's possible to hold the German advance indefinitely. However, to beat Germany, France has to get through all that provinces you turned into dust, suffering the same problems that held the Germans.
It's far better, to hold Denmark - conquer before war, put some strong forces (10-15 divisions) on the border, and push till the first river immediately. Germany will delay France for a year or so (Sitzkrieg), while bombers from Danish airports could perform Logistical Bombing over Berlin (it's not the infra what matters here, but the supply/fuel dump, which also gets destroyed by that mission. At the time Germany attempts the Sichelschnitt, those Panzers stop working just after the border (and as it comes to pure manpower, France is even better than a pre Barbarossa setting, so it should be a cakewalk for them - especially if you continue bombing Berlin).
Just a little tip: a nice movement for UK is to land in North Eastern Germany just in time for war, quickly expand the beachhead, storm Berlin, wait till midnight and pull your guys back (you've emptied the German resource/supply/fuel stack with that movement - they'll never get to full capacity again, especially in TFH).
You dont destroy the supply network of the enemy by destroying infra in the capital.