Woo - namecheck!
I'm not there yet, but definitely check out Southampton - you can combine German with another language, film, history etc., and it has a fantastic reputation - with languages being a strong point. It's also a Russell Group uni, which you referred to in the op, and it's not too far away from Sussex.
If you're interested in a language-based/linguistic-y course, then you could do German and Linguistics at looooooads of places. Southampton offers a German (Linguistic Studies) course, which combines learning the German language, learning about German linguistics such as German dialectology and how German has changed as a language etc., and learning about general linguistics not specific to any language, such as child language acquistion, and discourse markers. I find not only languages fascinating, but
language as a concept fascinating too - which is why this course is great.
Check it out. I'm doing French and German (Linguistic Studies) btw.
Having a look at the German page shows that there will be lots of opportunity to study cultural modules, but not any compulsory literature. Modern Languages is very contemporary at Southampton. Anyway, the straight German course there offers lots of options in History, Culture, Literature and Linguistics - plus the chance to do units from unrelated courses such as Philosophy or whatever.
Also, Southampton has a unique language stage system, whereby your progress in the language is give a 'level' from 1 to 7, with 1 being ab initio, 4 being A level stage and 7 being near-native fluency , which makes tracking your progress and achievement all the more easier.
Another link for you:
http://www.humanities.soton.ac.uk/courses.asp?type=1&sbj=40Anyway, that's all I know. I've totally forgotten all the info about the other mod langs courses