Blue Gender, Flag Recommendations
Both are helmed by legendary director/creator Ryousuke Takahashi, both have exquisite animation and feature mecha.
The Mecha genre is treated more of a way to connect into the soldiers minds directly, than being used in awesome cool fight scenes(though that happens too!)
FLAG is significantly realistic in setting, tactics used, and storytelling.
Blue Gender has sc-fi aspects that blend into it's story. It also contains explicit content.