I really don't understand why Hamburg is kept out of the discussion. As a previous post made it clear (and I totally agree), Americans always have in mind Munich since the US occupation was there. Hamburg remains unknown for the major part here.
To answer your question, I suggest Hamburg, of course not because I live there.
I spent many years in Munich and I am currently living in Hamburg. So I can help you well on this!
Let me start by saying that in my opinion BOTH Munich and Hamburg are Germany's most beautiful cities.
- Location: Munich has the Alps for sure. We got it. Its closer to southern Europe as well. But Hamburg has nice day trips, to the Harz mountains, but especially to the Baltic Sea (which is Germany's sunniest region). Of course, the swimming season is only July and August. But you don't have to swim... The Harz "mountains" are also relatively close to Hamburg, if you are looking for interesting topography.
- Weather: I always tried to convince myself that Munich has the best weather in Germany because I was constantly brainwashed by the Germans. They keep on saying that Munich, the southernmost city they have is sunnier and warmer than the cold flat North. That is absolutely not true. Actually, big differences between German cities in terms of climate can't be really felt. Munich has a lot of rainy days, especially in spring and early summer. Because Munich lies just on the foothills of the Alps, grey clouds are stuck over Munich, so expect to have this "anhaltend dauernden Regen", the Germans keep on talking about. Its like a stretch of at least 3 days in a row with nearly non- stop rain. The Danube and the surrounding region of Munich got always flooded every year (Bavaria and Sachsen have lot of rain in this time of the year). In the meantime, it is usually sunnier in the North. That because northern Germany is subjected to stable high pressure (located usually in Scandinavia) more frequently than the south from April to June. Bavaria (Munich) and Sachsen (Dresden) are normally subjected by low pressure systems from the Balkans. Temperature- wise, the south sees more fluctuation in temperatures, the north is more stable. So it is a few degrees hotter in the south when its sunny and nice but colder when its raining. In summer, Munich is 2C warmer than Hamburg but it rains a bit more. During fall, Munich has better weather though: it rains less and its sunnier than Hamburg (October- November). In winter, here it depends on what one prefers, if you like more snow and sub-zero temperatures, then Munich, if you like cloudy milder weather, than Hamburg. In Hamburg, it rains more in fall and winter but it is milder than Munich... Another feature of Hamburg is the wind, which makes the temperature in winter colder (so probably 5C in Hamburg would be felt like 0C in Munich, not always but this was my impression).
- Culture: they are totally different. Hamburg is more individual (like each neighborhood has its own people and culture), in Munich, its more homogeneous culture, where all people living in the city are the "same" (culture- wise). Hamburg is less conservative, since they have their red district etc. But this is where for me, Munich does better. Its cleaner...
- Salaries: in Munich, they are higher.
- Work: easier to get one in Hamburg. In Munich, it is mainly IT, finance and engineering. Hamburg is IMO more variant: pretty much everything and for everyone but mainly commercial (project management, consulting firms,... because they have the port etc)
- Architecture: more interesting in Hamburg (more modern buildings, more construction going on). Munich is conservative and homogeneous, which I find really good (but boring). Again, here, the factor "interesting life" plays for me a big role when I want to choose moving out.
- Quality of Life: Munich (neater, better salaries and services)
- $: Munich is more expensive (so if you gain more money in Munich, you are going to spend more. Important here is to look for the value of your money. Hamburg has it here better. You can live better and because you have different neighborhoods, you got to spend your money like you want. In Munich, its everywhere expensive. Especially the rents are more expensive in Munich (sometimes you get the same apartment with all same features and services in Hamburg for 100 Euro cheaper).
- People: in the south, more "locker" (easy- going), in the north more formal and business- oriented. In Munich, people seem to be friendlier to foreigners (because they are more used to tourists and internationals than in Hamburg). But in Hamburg, even if they seem a bit reserved at first, once you got to know them, they become astonishingly friendlier.
Happiness index: Hamburg. I am so happy here. Every year, the statistics show that the most happy Germans live in Hamburg. Even if I love Munich, I have to admit that I am happier now in Hamburg as I was in Munich.
- English language: disappointed with Hamburg. People are not used to speak it or hear it, so they really stare at you when you speak it. They try to avoid speaking it... not really international oriented in my opinion. In the south, I mean Munich, they are better international- oriented and speak English better. More understandable towards tourists. Education level in the south is anyways stronger than the north. Best universities are located in BAY and Ba-Wü.
- Food: more fish in the north, more meat in the south. Not really fan of German food, so it doesn't matter in which city. For me Hamburg has it here better because I eat more fish than meat.
In general, Hamburg is more interesting, more variant (only down FOR ME is the non- conservative culture (not really a lot of old architecture and beer culture like the south, where people sit together, talk and laugh, more understandable toward internationals etc.). See, even if the salaries are higher in Munich, you got to spend better your "lower salary" in Hamburg than in Munich. You got to be really happy here. Don't worry for the less friendlier Hamburg, once you meet them and got closer, you will be surprise by how nice they are (do not judge on the first impression, you are not a tourist here, you are going to live here, you should think for the long- run)
Good luck choosing "your" German city that fits your personality the most. But anyways even if I listed the meticulous details for both Munich and Hamburg, there is not really a bad choice to made here, both are great!