Fates was a pretty good game, and although it does get quite a lot of hate, there are plenty of things that made it an enjoyable and replayable experience.
-Fates has an amazing soundtrack. I personally think that it has the best soundtrack in the series.
-Gameplay was done really well, and they balanced the pair-up features so that one pair couldn't completely dominate the battlefield.
-Character customisation both cosmetic-wise and stats-wise made each replay of the game unique.
-The majority of the characters are actually somewhat interesting, despite having cliché personalities.
-Capturing castles was a great way of opening up Corrin-only runs (though I don't think that was their main intent).
It's a shame that the plot/story of Fates was so flawed, because I believe that's one of the main reasons that caused many people to view the game as 'bad', which isn't the case.