I'll admit that I haven't gone yet, but the next time I book plane tickets for roller coasters, it would be to Germany (and Austria, Switzerland, Poland and the Netherlands) hopefully in 2020. Of course I'm going to exclusively amusement parks. I'll fly into and out of Frankfurt, and the German stops would be (in alphabetical order, not the itinerary order):

-Bayern Park

-Belantis

-Erlebnispark Tripsdrill

-Europa Park

-Fort Fun Abenteuerland

-Freizeitpark Plohn

-Größte Kirmes Am Rhein (I would do Oktoberfest, but Olympia Looping and Alpina Blitz always go here every year and it's during a time of year where the parks are open longer and the weather is warmer so the rides will run faster.)

-Hansa Park

-Heide Park

-Holiday Park

-Legoland Deutschland (maybe)

-Movie Park Germany

-Phantasialand

-Skyline Park

-Wild-und Freizeitpark Klotten/Cochem

I do have some questions, though:

1: I want to also eat at good local restaurants along the route since many of the parks close at 6:00 PM. I was looking at what was listed on Yelp, and while it does provide results, I have noticed that it has probably an order of magnitude fewer European commenters/restaurants listed as compared to this side of the pond. Is there an equivalent to Yelp that has a greater number of European users?

2: Gasthöfe are a lot more common in Germany than the US. Do the highly rated places under €60/night commonly serve coffee with their breakfasts?

3: Americans are very friendly towards strangers, and it's extremely common over here to let their dogs say hi to new people all the time if they are out and about. I'm kinda completely obsessed with dogs, so is it okat over there if I ask strangers to say hi to their dogs or will the humans want to avoid me like I'm a White Walker?