Looking at German, amongst the Germanic languages, it's relatively conservative grammatically speaking.
It has 4 cases of noun and pronoun, 3 genders, and six verb forms (5 distinct, usually), declined definite/indefinite articles, a useful singular/plural second person pronoun distinction, inflected adjectives for case, gender, and number, productive comparative/superlative suffixes, present/past indicative and subjunctive, and relatively well preserved strong and weak verbs.
My question is, if other Germanic or even Romance languages were as conservative as German, how would they look today? If English, Danish, Norwegian, Swedish, French, Spanish, or Italian were as inflected as German (relative to their respective parent languages: Old English, Old Norse, Latin), how would they look?