The verb-order inversion is usually not the hardest part of German -- in fact, it's one of the trivial things to get used to.

My trouble with German are that the same endings are overloaded and reused in different cases (I have no trouble with cases: English has cases too, and retains the nominative and genitive).

German is mostly consistent, but the endings to me are like operator overloading gone wild. The endungen like -e, -en, etc. overlap in so many cases. For instance -en is plural definite in all cases, but also also in dative/genitive definite cases, and indefinite masculine accusative, indefinite plural dative, and indefinite masc/neut genitive.

If you aren't fluent in German, it takes a bit of effort to disambiguate the endings, and to me it seems needlessly difficult. If only different endings were created to disambiguate.... (e.g. -et, -ew, -ep, etc.)