After airbases established, Iceland would be no different than Norway where ships protected by Luftwaffe.
Aside from being more isolated, harder to resupply (you can't catch a train there...) and thus more vulnerable to any counter-stroke... all while drawing German assets off.
France more modernized as regards machine tools etc than Hungary, easier to produce there than Hungary. yes, workers available as evidenced by the ME 210 being built there.
Labour wasn't always as tractable in France as it was Hungary... you know, since it was occupied territory or under the Vichy government
. Your ME 210 example is like a drop in the bucket compared to your mass truck production concept. I see you've already given up on the earlier idea of Poland as an industrial colony. I've also yet to hear how you intend to re-tool foreign factories to churn out German designs to German specifications. Comparing France and Hungary is all well and good, but the comparison needs to be with Germany.
And, like all of your other ideas, you haven't put forward any explanation as to how this would come about. Without even the pretense to explain how these war winning changes could come about, there isn't any real value to this discussion. It's just a wishlist, where even the vaguest plans could have worked if only "something". Or any minor exception can be blown up into a continental scale policy. Scenarios where any impediment can be waved away.
Okay, Germany wins because of some improbable (material and/or organisational) change. What now? Is that the point of the post, Germany wins by virtue of magic wand? How boring.
Strategically they did quite well at Desert warfare, British weren't able to win any decisive battles against em for 18 months.
Rommel had no strategic accomplishments in the desert other than stopping the Italian collapse in 1940, and notionally tying up the British. Given they had few other theatres to fight in, I wouldn't count that frankly. On the other hand he captured nothing of value, and often had to withdraw and abandon what little he did capture. Not a single victory of Rommel's was decisive, because the strategic context was that without massive defeat, even annihilation (or the loss of all their resupply points), the British could always replenish. Rommel's force however was whittled away, something he couldn't afford in the strategic context. Much of this was because of poor logistics, which as well as being a material issue, were also a result of bad organisation... which is something that comes under strategy.
Allied tactics in the desert were generally poor, but their strategy played against Rommel's weaknesses and their strengths.