Yeah - I don't think it's oversaturated (at least in CGI, more anime stuff like that). Interesting to see a historical accurate setting - I know I wouldn't be able to stop myself adding fantasy elements
. What year are you setting it?
It's around High Medieval age, but is a tricky question because there is some fantasy into it, because events take place in made up countries (the Holy Roman Empire Across the Sea), and there is some discrepancies with how exactly things go in Europe (Is a sort of alternate reality) The important about historicity is the tone.
some shots:
Anyway the post is not about me, but there is quite enough you can make a game off about different time periods without the need of going fantasy at all; It is nothing bad to put fantasy in any setting (like, FTL in space, Mindpowers in modern, Elves in medieval ages), the only important is not putting that in the game because you're out of ideas x'D
To the OP I'll say that once one start writing the script and the characters talk with their own voice and is not work at all making the story, is the right game you have to make.
If you ask the community they'll say "there is not enough modern theme games!" xD But I also can say that If I were not a 3d modeller in order to make my own assets when needed, It is more difficult to do anything different from modern.