So this question is far too broad for me to even attempt to answer, but there's multiple things I want to explain that may improve your understanding of the Third Reich and it's institutions.

First, calling the Nazi Reich an Empire along the lines of the colonial British Empire is a fallacy. The Nazi's occupied a wide swath of territory mostly in continental Europe over a period of five years, and held it solely during a time of war, but they didn't establish anything close to the stable bureaucratic administration Britain or France did over their overseas colonies. German rule across its occupied lands varied significantly, from Austria, which was incorporated directly into the Reich, to Czechoslovakia, which was split in two and made a semi-autonomous rump state, to France, which had the puppet Vichy government installed, to Poland and Russia, which faced incredible brutality and were used as little more than sources of wartime labor. German policy towards occupied nations also changed significantly throughout the war, generally becoming more brutal and more extractive as defeat began to become more and more likely.

And adding to that, it's not fair to say that Germany controlled all the wealth and resources of the countries it occupied. For example, with occupied France, while Germany was essentially extractive, and did things like artificially fixing the exchange rate of the Reichsmark to gain favorable trade relations, it still was forced to respect native institutions and trade relationships to some degree and cooperate with the French government. Similar terms were struck with the Dutch, and so, even during the war, Dutch corporations like Philips, Shell and Unilever remained not only independent, but also continued non-war oriented production.

And finally, comparing the wealth of empires is an incredibly difficult task. What metric would we use? An obvious one Gross National Product but it's imperfect because the amount a country produces doesn't mean the average citizen has more prosperity (look at India). We could look at income per capita, but this favors smaller nations over Empires, and wouldn't really achieve the comparison I think you're looking for. This leads to the deeper question: what's meant by wealth? The way you've phrased the question, it sounds like you're asking about power, which is again different.

To conclude, I'd try asking a more specific question, being mindful of the vagueness of the term "empire" and the difficulty in comparing "wealth" between nations.

As an addendum, I refer you to this post made last month by /u/commiespaceinvader, who talked about empathy in history; specifically, about understanding that a large part of a historian's job is giving voice to the silent and the repressed. The Third Reich was a nation and ethos that gained power on the backs of slavery and genocide, and questions like this that glorify the "achievements" of that institution neglect the very real human suffering the Nazis caused, and implicitly devalue the experiences of the many people that faced unspeakable horrors under Nazi rule. I'm not accusing you OP, but it's something to be mindful of when asking questions.