My opinion is that Germany's lack of a true heavy bomber and an effective long range escort fighter were critical to her defeat in England.
The heavy bomber issue revolves arounfd two sub-issues....the lack of defensive capability, and the limited warloads that could be carried. The inadequate defensive capability isnt so much a lack of guns, rather the lack of turretted defences. Perhaps you guys will disagree with that, but IMO German bombers were vulnerable. British fighters found it relatively safe to close German bomber formations to relatively close ranges, with no great threat posed by the bomber defences. This was the primary purpose of those defences.....to keep the attackers at arms length, and thereby reduce losses. The US B-17s and B-24s were the best at this. British bombers were less capable, though it needs to be acknowledged that night bombing was done with a stream, and not a defensive box formation, which inherently reduced the effectiveness of the defences.
With regard to lack of warload, figures are often misquoted for german bombers. Their maximum warloads are impressive, and are often quoted as what could be carried. But a closer examination shows that at the ranges the germans were engaging the RAF, the bomb loads were often much reduced. Typically a german bomber might redcue its warload to 2000lbs or sometimes even less. This just was not enough to be effective. Put another way, you would need about four times as many German bombers as you would British ones to be effective. That means to match the firepower of a 1000 bomber raid, you would need 4000 german bombers. The germans never had the ordinance delivery to undertake a true city busting strategy...
With regard to Night bombing, the germans had superior navigational technology in the beginnig, and the british defences were woefully weak for night combat. Whilst I acknowlwdge the many differences, I do think the german beam riding technologies are similar to those developed by the British later on, and found to be very effective....lioke OBOE....So the ability of the Germans to hit city sized targets at night in 1940-41 was actually pretty good.
However the British were rapidly developing their night defences, such that about March 1941, it was becoming unecomic for the Germans to continue massed night operations. By that time their bomber losses could be counted in the hundreds, and the LW simply lacked the replacement system to maintain those sort of losses....
So we dont really know what might have happened if the Germans had developed a proper heavy bomber, and an effective long range escort fighter. I think it may have made a difference to be honest. Better defences, bettter war loads, greater losses for the RAF....these are all factors to consider.
German bombers . true