Vandread, Simoun Recommendations
You should give Vandread a try if:
> you enjoyed the gendered aspect of Simoun's worldbuilding but wished it was furthered developed, explored the other side more, and had interactions beyond fighting & "the war";
> wished for a more eventful plot than patrol missions;
> wanted to see more variety in mecha/vehicle design.
I rewatched the beginning episodes of Vandread for this, and I'd recommend giving the first 3-4 episodes a watch as you'll get a pretty good understanding of what to expect from the rest of Vandread's 2 seasons. If you enjoyed the first few episodes, you'll probably enjoy the rest.
It's also got a decent