The logo should incorporate the American flag or at least the colors of it, red, blue and white to show that "Oktoberfest in July" is an American thing.
The slogan is not a must and the logo should work with or without it.
To give us an idea of the overall feeling of your brand, let us know which styles you lean towards
I want "Oktoberfest" and "In July" treated as two separate objects, so that "In July" stands out by itself.
There are many Oktoberfest logos out there (https://www.google.com/search?tbm=isch&sa=1&ei=rmfHXNfhBZCxggf-sZWQDg&q=oktoberfest+logos&oq=oktoberfest+logos&gs_l=img.3..0.13235.18167..19000...2.0..0.132.1226.15j2......1....1..gws-wiz-img.......0i7i30j0i67.3MqR51QU76k )