If you liked the Blue Gender anime, the Anime-Planet community thinks you'd like:
Ayato Kamina may seem like an average boy in a devastated world, but after being captured by TERRA, a military organization set on saving the world from the Mu, an alien race set on "tuning" the world, he realizes he is an instrument in deciding the fate of humanity and piloting RahXephon. Not only is Ayato the only person who can control the mecha, but he also has a terrible fate of his own. Holding onto memories of his old life and grasping to keep his own humanity, he must struggle in this new world and realize his true potential with RahXephon.
In the not-so-distant future, mankind is at war with itself. The lives of Chise and Shuu are torn apart when Chise is chosen to become the ultimate weapon to fight for Japan against their enemies. Death, sadness, and the hardships of love accompany Sai Kano in its grim look at war and its consequences.
Sai Kano is also about the world coming to an end. In both of these anime there are main characters that die; this creates an uneasy feeling when watching them. Who will live? Who will die? Will the world fall into utter destruction?
It is the year 2023, 30 years since the time of the Silent Crisis that brought the world to the brink of destruction. In the present, other-dimensional beings known as the Lucifer Hawk are running rampant, and threaten to take over the human world. The only hope for mankind is the AMP -- the Attacked Mystification Police -- a group of women with paranormal abilities who are dedicated to stopping the Hawk at all costs. With the frequency of attacks increasing and the bodies piling up, it's up to Katsumi Liqeuer and the rest of the gang to stop the invading threat... before it's too late.
Ten years have passed since the demise of the bubble economy, a time that polarized the world into two groups of people: the rich and the poor. In the present day, Saiga Tatsumi (a former war photographer) has been hired to investigate a secret club for the rich named the Roppongi Club, but he soon discovers secrets much darker than he’d ever imagined. With the help of a exploited goddess named Kagura, Saiga now possesses the power to kill by simply taking a photograph; but can he stay alive long enough to save her from her captors?
Juan "Johnny" Rico lives in a time when humanity is on the verge of a war with a relentless, invasive enemy: the Bugs. Against his parents’ wishes, Johnny enlists with the armed forces and is placed with the Mobile Infantry, where numerous hardships await him. Meanwhile, Johnny’s friend Carl also enlists as a researcher, and Johnny's love interest, Carmencita, is acting as a pilot in the navy. Collectively, these friends will try to stay alive while fighting an endless struggle against the enemy.
While This recommendation may seem a no brainer on one level, there is more in kind between Starship Troopers and Blue Gender than first seems obvious. Both stories resonate on a human level of the battlefield. Jhonny Rico's struggle and shock of true battle with the bugs mirrors the sheer terror and displacement that Yuji feels when he is thrust into a bloody future War that he has no real stake in save his own survival. While Jhonny loses his innocense in one way (the more conventional but not any less jarring shock of wartime), Yuji loses his in another (A more literal way due to the societal norms of the future brought on due to the war with the Blue). Both stories also follow a love interest that whileat first is unrequited, more develops over time in a way that serves the story without taking center stage. Both very recommended for any Alien bug Vs Humans with mecha drama lovers.