Ra-Sen group made its visual novel in 2008 and won Japan's Sendai-Miyagi Animation Contest
I like Sengoku Era based anime, plus it isnt a traditional hack and slash battle, but using a mecha (cool!)
Date Masamune
Date Shigezane (Masamune's cousin)
Katakura Kagetsuna (Masmune's retainer)
Megohime (Masamune's wife? Not sure)
The characters has a good design IMHO. Date Masamune always using an eye-patch in many series, Samurai Deeper Kyo, Sengoku Basara, and Samurai Warriors. Well, that's based on the history of course
The mecha design is kinda....... out of my imagination. I thought it will look more cool ^^