I actually liked FE8, not that it is hard, but I like the promotion options. Just don't use Seth and never grind, it will be okaj. I actually always skip the story plots, so don't ask me about those.
FE7 is good, but a bit long for my taste. FE10 is nice, but makes leveling up most characters actually hard. FE11 is rubbish. FE9, never played it, but heard great things about it. Main problem is, you probably can't get a NGC anywhere nowadays, even if you could, you still need to track down this game.