Meanwhile I'm completely out of the loop here because I've never played a Fire Emblem game in my life.
I've talked about trying them before, but it's been a very long time since I've done so. And as evident by the above, I have yet to actually try one.
I'm at least curious enough to give one game ago. Can anyone offer advice on which game would be a good place to start?
Download Heroes for free on your phone to get a taste of the general gameplay of Fire Emblem. Granted, Heroes simplifies and has its own spin on things, but being free, it's a good intro to the gameplay.
Shadow Dragon on the DS if you want to play the first game (Shadow Dragon is a remake of it). Marth is from this game.
Blazing Sword (simply "Fire Emblem" in the west) for the GBA if you want to play the first FE game to be released in the West.
Awakening or Fates Birthright on 3DS if you want something generally easier but still has content to make up for it.
And this may be an unpopular opinion, but I think Shadows of Valentia on 3DS is a good start. It's pretty unique within the series, but it has top notch presentation, particularly in the voice acting, and the writing is fantastic with some really charming characters. IMO, this makes the game easy to get invested in. Of course the gameplay is great too.