German PhotoLine is great, it is a budget priced, high-end alternative to Photoshop with tons of features, highly configurable. For 60 € you get both a Mac and Windows version, language can be German or English or a lot of others. Only draw back is the absence of tutorial literature. But there is a manual in German and English, and a very responsive forum, also in English, even though the main forum is in German. Trial download on pl32.de.
Usual disclaimer applies.
Good light!