This game fixed a lot of the problems I had with the first one. Your energy blasts can be done more reliably in mid-air to an opponent on the ground and you can transform in the middle of battle, or you can choose the fused/transformed version at the start.
I'm glad to see this storyline play so well too. In this game, you basically hear voiceovers as you fight and before battle, even by characters off screen. Another thing that is nice is the fact that you can change characters in the tougher battles that had multiple people in the storyline. For example, you can switch from Goku to Piccolo when you fight Dr. Wheelo in the story mode. The only thing I didn't like was that they skipped some battles, but we've seen the same story so many times that it's understandable.
Also, the concept of changing history is ambiguous; like if you beat Nappa with Tien, not much changes. Fortunately, none of the biggest battles are skipped in the story mode. I want to also note that the difficulty fluctuates and feels better than the original since the fights in the story mode are like a combination of battles rather than stall this bad guy for 1 battle, and beat him in the next; it feels more fluid. Then of course for kicks, you can always try to win on this really hard mode to impress yourself. They also briefly touch Dragon Ball GT and the original Dragon Ball, which is a nice touch too.
The graphics of the game make you feel like you are watching the show as well as the voice acting. The in-game transformations look good too. It also had a couple of good themes to listen to.
I like being able to counter a lot easier than in the first Budokai Tenkaichi game as well as smash them into attacks and rush them again for a while. The issues I had with the game are that the charging can sometimes be an issue with moves that you do not charge for. Basically, you and your opponent on rare occasion (like missing the ground opponent with an air Kamehameha), can fire energy blasts at the same time but the one whose energy blast goes off last will be hit while he or she is still charging.
I do like the guard crushes you can do in addition to how max power lets you use more vanishing attacks (smash opponent flying and pursue them more times) and the boosting/extra charging of some moves makes characters play differently enough. The versions of the same character are interesting too, like how Goku from the Saiyan Saga has the Kaioken move eat up extra energy compared to the version of Goku in the Frieza Saga who can go Super Saiyan and finally the Cell/Buu Sagas in which Goku can go to Super Saiyan 2 or 3.
A new move they added lets you push away enemies at the cost of life to help free you up. It's like a combo breaker and is a nice touch when you're not getting off that strict timing of dodging attacks and countering.
They added a ton of characters to the game, some of which lack energy attacks (such as Arale, who had a Dragon Ball cameo; she was from Akira Toriyama's, the Dragon Ball creator's, Dr. Slump manga), or cannot fly (they do repeated mid-air jumps but descend while not punching/kicking, such as Yajirobe). The only other complaint I have is that the game takes about 10 seconds to load a battle. Another nice point is to mention that the 1st form of Cell cannot absorb life from androids because they're not organic. Also, androids do recover energy on their own rather than charge it up.
Still, I thought it was worth playing because of the modes. In addition to the standard tournament and story modes, you have a Sim Dragon mode which is appropriately named; you live out 10 days in 1st person choosing to train, explore or rest.
I found it to be a better challenge than the Ultimate Battle 100 from the 1st game since they did not give latter enemies a ridiculous amount of health so that only the most damaging characters have a chance at winning. In Sim Dragon mode, you'd need some luck with your training or play a minigame and it does take some strategy too, such as training consistently in 1 area, getting a feel to when to train to the limits (if it fails you lose a lot of stats, or if it succeeds they go up through the roof) or resting when you're somewhat tired (below 70%). The battles are challenging too. However, I find survival mode to be rather repetitive as you have to fight 50 guys, one by one and most of them are a breeze until the last 10.
I think the game had much more replay value than the 1st one as well. There's also Mission 100, which I think is a good idea since you can play with teams of characters (sometimes they have you use less DP, Destruction Points as a form of balancing, such as The Legendary Super Saiyan Broli who's really powerful costs 9 whereas Nam from the original Dragon Ball costs 2) and you don't always have to stick with using the same character. Also, if you have a prior Budokai Tenkaichi game, you can use Disc Fusion for some other modes via Disc Fusion. I do think that DP battle for 2 player is a great balancer too.