'The RN would have defeated Sea Lion; the RAF stopped from from even trying'
An interesting point. Given the interwar focus on 'bull' and the whitewashing of inadequacy after Jutland, the RN may have struggled. Rate of fire (which was measurable and enabled Captains/gunnery officers to progress through the ranks...) was placed higher than accuracy - a weakness cruelly exposed by the Bismarck and Prince Eugen in 1941. Additionally, who's to say that a refreshed, victorious, Luftwaffe would not have done significant damage to any RN sortie into the channel? Perhaps Repulse and PoW would be sitting on the floor of the Channel instead of off the coast of Malaya?
One thing is for certain, without air cover and with a U-Boat / E-Boat screen the RN would have taken heavy losses attempting to repel a German assault - at what stage would it have been a strategic decision to preserve the remnants of the fleet to continue the fight from the Dominions? The proposed landing beaches near Brighton would have been used to land an initial wave (though challenging due to a lack of specialist craft) and the plan would have been to capture Shoreham/Newhaven as soon as possible.
Back on Thread. The Spitfire/Hurricane et al combo saved us from finding out if the RN could have closed the Channel; for the rest of the war I pick the T6 for being the machine which prepared the crews for frontline types and the C47; much like the CH47 today, an unglamourous but vital aircraft. In all Theatres in several roles the C47 delivered.
But the Mosquito is beautiful....and looks do go a long way!!!