Acknowledging how different the two are, I shall try not to compare them too often.
Fullmetal Alchemist, in terms of its animation, is actually quite good. Disregarding the time when it came out (2003), it is a generally well animated show. Some of the action is pretty well choreographed, though most of the show is not as action-centric as the shounen tag may imply. The same can be said for the music used in the show : Dante's theme (if that is the official name) is one of the most haunting pieces I have heard. And, believe it or not, they even use Beethoven's 5th Symphony (or at least that's what it sounded like) near the end, which is surprising considering they're in London for that particular scene. I had forgotten how good these openings were, especially Melissa by Porno Graffiti.
Now the main complaint people seemingly had against it - the story. The first few episodes were direct adaptations of the manga, with the sequence of events rearranged, or in some cases, fillers that tried to establish some relation with the main storyline. Even then, the Majhal and Psiren episodes were pretty entertaining to watch. Ed and Al have a borderline obsession, first with bringing their mother back to life, and then with getting their hands on the Philosopher's Stone. There are certainly issues here - the pacing, at times, is terrible. However, with time, the writers really come into their element with how the plot is supposed to progress. It sets up the Ishbalan conflict, Liorian revolt and the Elric Brothers' past simultaneously, and does not forget to make it engaging and well constructed. Marcoh's desertion, Bald's attack and Scar's brutality are all brilliantly depicted.
The main essence of this show is in the second half of the story. The reality of the Homunculi's existence, and their desire to be alive again, are some of the best story plots I have seen. Envy's hatred of Hohenheim, Dante's past and the recreation of the Ishbalan War all invoked a sense of discomfort and disbelief in what was happening. Edward's sacrifice to achieve his lifetime obsession of bringing Alphonse back is, albeit confusing at first, pretty satisfying to watch.
One of my main problems with this iteration of Fullmetal Alchemist is that, while it has some amazingly constructed and well built-up characters, also uses others underwhelmingly, not giving them the screentime they deserve. A fantastic example of this would be Greed. He is formally introduced only 6-7 episodes before his death, and despite being an interesting character, spends most of his time walking around with his hands in his pockets and being cocky. His death at Edward's hands hits hard, but not nearly as hard as it could have hit had he been built up better, especially because we know nothing about him apart from the fact that he is a good leader and is, for some reason, against the Homunculi (again, not explained). Similarly, Hohenheim is built up as this bad father, is there for 2-3 episodes as a chill character, and then straight up disappears till the end. Another problem I had was with Mecha Archer. I'll leave it at that. Some of the storylines also keep going in circles until they somehow exit that loop.
In conclusion, while I firmly believe that the original series is overhated beyond disbelief for its divergence from the original manga, I also must acknowledge how many parts were flawed, while others were brilliantly executed. I firmly believe that Alphonse's monologue about equivalent exchange from the original series should have been included in Brotherhood. What we got, though, was still much better than what it is made out to be by the masses, and it should be accordingly appreciated.
