it will be really nice to see more of the gorgeous art that has been created for this game and see the story brought to life. i expect to really enjoy this stuff.
however, i'm not sure if it's the best use of resources. most of us never played the campaign that shipped with the original game, and even (in the best case scenario), that the campaign and sandbox games were integrated as i always hoped they would be (both in elementa and gal civ 2) most will surely end up skipping the cutscenes after the first or second playthrough. in fact, i am unlikely to play the FE campaign either, unless it is as deep and open as the sandbox (or better yet, the same game).
moreover, if you want to compete with the best, the production values will have to be really good. can you honestly say that people wil enjoy your cutscenes as much as they do in mass effects? (and if so, great). i thought the narration on the opening sequence in WoM was really cringy (the one on the website though, with the female voice, was much better).
moreover, are the peope who want that, emotive immersive rpg experience really going to play what wil (hopefully) always be a hardcore turn based strategy game? i know that the game already has rpg elements, but to my mind these make it more hardcore, not less, because of the amount of extra micro they add.
i love rpgs, but it is important to play to your strengths and know your audience (present and target). i'm not saying don't make the game more immersive, but don't do anything that you can't do as well as, or better, than anyone else. by this i mean, cutscenes, power poly graphics and animation, expensive narration or any other kind of production values that "take over" the gaming experience and interrupt gameplay. some good examples: the baldur's gate games have beautiful handpainted graphics, but next to non-existant animation and bare bones narration. but they are as good games as the newer rpgs because of their greater flexibility, depth and shear size. they did what they could well and avoided what they couldn't. or if you want a more recent example, indie smash Braid. gorgeous art and music, 0 narration or 3d animation. you are never forced to take a break from the basically fantastic game experience.
this is not to say what you're doing is a bad idea. i wil enjoy everything you add to the game, i just hope you play to your strengths.