Milch/WW, I'm thinking of planning a Germany trip soon. Any recommendations on places to visit/best time of the year?
Depends on what you want. I tend to think that every country's big cities are somewhat similar, but Berlin definitely has its own vibe. If you like partying, you should definitely get lost drifting through the night once. Don't waste too many days on it, though.
Hamburg is the best big city to me. Just the right size. Also, I wanna meet your fat American ass there. Could show you around a bit for sure, especially if you're into beer.
Munich is what you expect. Really nice.
The one city I'd tell you to avoid is Stuttgart, unless you're the biggest fan of cars.
Region wise, I fucking adore Franconia. Has all the beauty, tradition and beer you'd ever want. It's also halfway between Munich and Berlin.
Honestly, I'd need more specific information about your needs.
I would definitely take the train to get around. It gets you everywhere and you get a much better idea of the country. Franconia, Bavaria in general, the Rhine area and Black Forest area all offer great views from the train.
Edit: Winters can be miserable in Germany. Especially in the cities. Probably best to avoid.