Any patience you had with the flawed first arc will be rewarded handsomely.
While Phantom Blood was dragged down by an extremely dull protagonist, an overly-evil villain, poor art, and a slow beginning, by the very first chapter Battle Tendency has already done away with half of this. BT picks up 50 years onwards from Phantom Blood, in the 1930s, and now follows the grandson of Jonathan Joestar, Joseph Joestar. While the two are dead ringers for each other in appearance, you would never mistake one for the other - they're polar opposites in terms of personality. Where Jonathan was noble, gentlemanly, and generically heroic, Joseph is brash, loud, and not afraid to pick a fight. On top of that, he's not just willing to fight dirty - fighting dirty is his defining character trait. Not that he is without a sense of honour, though - his reasoning for picking fights is always noble (well, almost), and does not hesitate to put himself in harm's way for a loved one. While this does, to some degree, make him sound like a standard idiot hero shonen protagonist, the key factor that sets Joseph apart from the ilk is that his attitude is misleading - he's incredibly smart and quick-witted, and always prepared. Joseph is a big fan of Sun Tzu's "The Art Of War", and it shows in his continued pragmatism in combat and his constant trickery.
I touched upon this in my review of Phantom Blood, but what really stands out above all else in JoJo's Bizarre Adventure are the fights. Whereas most shonen series will rely on delaying the protagonist's appearance to increase plot tension, or using a convoluted string of powerups to justify the protagonist's ability to win, JoJo's Bizarre Adventure is all about the tactics. The biggest strength in this is that the question ceases to be "who will win?", or "when will they win?", but "how will they win?". The problem with the Phantom Blood, however, was that while this sometimes happened, Jonathan wasn't the kind of character who would intentionally use deception, which highly limited what ways he could achieve victory. Joseph, however, is deception incarnate, and as a result Battle Tendency is truly able to shine. There really is no better representative of JJBA as a whole than Joseph Joestar.
While JJBA is more driven more by fights and characters than by plot, Battle Tendency is nonetheless an improvement on the first arc in the plot department. In the very first chapter, things immediately escalate with the discovery of an ancient man inside a stone pillar... surrounded by dozens of copies of the vampire-making stone mask from Phantom Blood. "Oh, shit" is the appropriate reaction here. What's more, the man inside the pillar? He's not quite dead. Nor is he quite the only one of his kind.
Another interesting point about how this arc compares to the first is that, in spite of the name "JoJo's Bizarre Adventure", the first arc really wasn't much of an adventure. After all, the bulk of the plot is divided up into three locations in Victorian England, and the setting in general feels very claustrophobic. But Battle Tendency truly lives up to this title. It begins in New York, but the discovery of the Pillar Men and his need for Hamon/Ripple training ends up leading him to travelling to numerous different countries. While the first took after vampire horror more than anything, Battle Tendency follows more in the footsteps of Indiana Jones movies than anything else.
While it is easy to ramble at length about what makes Joseph far and away one of the best characters in JoJo's Bizarre Adventure as a whole, he is far from the only good character in this arc. Erina, Straits, and Speedwagon from the first arc are all still present, with the latter ironically being more useful in his old age than he ever was in Phantom Blood. But the real stars here are the new additions. Joseph gains allies in two Ripple users who are both his senior - Lisa-Lisa, the master of a school of the Ripple in Italy, and her disciple, Caesar Zeppeli, the grandson of Jonathan's master. Caesar is definitely the standout here - while he isn't quite an amazing character in his own right, his aloof and cultured nature is a direct opposite to Joseph's, and the two clash wonderfully.
On the opposite side of things, we have the Pillar Men. These three serve as the main rivals to the Ripple warriors: Wham, ACDC, and Cars. Cars is the leader of the three, and is one of the few things I fault about this series - his motive and overall personality are quite generic for a villain. While Dio was also overly evil, he was extremely fun about it. Cars doesn't quite match up - however, he doesn't need to all that much, because the real rivalry here is between Joseph and Wham. Ironically, Wham is the lowest Pillar Man in terms of Hierarchy, serving behind their leader, and his right hand-man, the strange and disturbing ACDC, and yet he's by far the most prominent of the three. Though all of the Pillar Men, like Cars, lack any value for life as most humans would, Battle Tendency makes use of him not being human. He has his own moral compass, revolving around the honour of battle. Wham values the honour of the fight above all else, making an interesting parallel to Joseph in the process. Though their powers are generic - the use of the powers of Wind, Fire, and Light respectively - in true JJBA fashion, they still manage to make inventive use of them.
Yet another thing JoJo 2 has improved upon is the art. Though it's still very rough around the edges, having some awkward muscle structures and overly thick lines in places, it's a firm improvement - and at it's best, it's downright eye-candy.
With all this having been said, it's hasn't completely patched up what mistakes Phantom Blood made - it still contains one key fault from the first that would not be fix'd until the third arc. Joseph is almost as much of a camera-hog as Jonathan, in that the vast majority of the fights revolve around him, which limits how good Caesar and Lisa-Lisa can be, especially the latter, as Caesar's interactions with Joseph do allow him enough screentime. Similarly, it helps greatly that unlike Jonathan, Joseph is a protagonist worth giving the spotlight to 90% of the time. Due to these two factors, it is a slight improvement, it hasn't fixed the problem.
However, this is merely a small scratch on an otherwise shiny diamond - it's hard to care in the face of how incredibly fun JoJo's Bizarre Adventure 2 actually is. Joseph alone is enough to carry this arc, but a more dynamic story, a better all-round cast, and much more focus on the intelligent action that is JJBA's raison d'etre rounds Battle Tendency out as one of the greatest highlights in JoJo's Bizarre Adventure.
Final Words: An improvement in every way. Arguably the best arc JoJo's Bizarre Adventure has to offer.
For fans of: Fist of the North Star, Toriko.