I just bought MLB 2005 for the PS2 about a week ago, and after playing it non-stop, I have my list of positives and negatives.
The Franchise Mode is stunning. I feel like Billy Beane. You control everything, and I mean EVERYTHING. Player management (which includes call-ups, send-downs, trading, line-ups, etc.), player scouting (a scout for each section of the US, and another for the international prospects), Food prices, concession prices, player equipment, coaches, managers, training, development, business management, loans, advertisments, and more. It's insane. For any aspiring GM, this is absolute perfection (or as close as any game has gotten).
There are good and bad parts of the gameplay. First of all, the hitting/pitching interface isn't that good. Hitting is either far too easy or far too hard. Unlike MVP, there's no ball marker when it's on the way to the plate, so it's nearly impossible to draw a walk (because everything looks in the strike zone). Baserunning is all right, nothing to complain about, nothing to compliment... Fielding is good until the ball gets near you. When you're near the ball, an autopilot of sorts takes over, and you can't direct him no matter what. He always catches the ball when it happens (save errors), so it's not like a detriment, but it's still annoying. Not great, not bad.
DEFINITELY a plus. In case you don't know what this is, you create a player (age 18-28) and give him a name, body, equipment, attributes, etc. With the attributes you're given, you can't really make anyone other than a below-average player. You break into Spring Training with a team of your choice (You have a better chance of signing with some teams than others due to position scarcity) and begin playing. After Spring Training, you are either dropped or offered the minimum contract (400/1 Yr.) You set goals for yourself (.250 BA in a season, 3 H in a game, 8 BB in a month, etc.) to complete in that season. If you're put on the inactive roster, you can request more playing time. You can ask to be traded at any time, but that doesn't mean you'll get either one. In fact, your team may be pissed off so much they'll just outright drop you.
You play through multiple seasons, earning attribute points for how well you do. As far as I can tell, a good game for a position player will earn you 2 att. points (1 in a simulation) and a good game for a SP will earn you 5 att. points (2 in a simulation). I haven't tried a closer or reliever in general yet. The more attributes you get, the more you improve, etc. etc. etc. You go through four levels (Rookie, Veteran, All-Star, HoF) and the difficulty heightens steadily the better you get. I've created two players, a starter and a second sacker. I've played more with the second sacker, a guy I named James Black who's now on the Yankees (what? It was the only offer I got, I had to accept). He's been on about ten major league teams, including the Blue Jays in their 2010 WS run. The Bosox broke their curse in 2006, the Cubs in 2011. This is for sure a great style of gameplay.
Minor Leagues/Rookie Draft
One of my least favorite parts of the game. There ARE no minor leagues, just an inactive roster, and the "Rookie Draft" consists of two rounds, the second round only going 16 teams long. I'd prefer the depth of players to be something like HH2004 or MVP2004, with all three minor league systems.
Other minor positives and negatives:
You can use the EyeToy to put your face in the game. You can also e-mail a picture of yourself to the PS2 people and they'll send it through the network adapter.
I've never liked the "bar" system of rating players. I prefer numbers. IE NBA Live 2004- Good, MVP 2004- Bad.
Some of the players are highly overrated and underrated. Timo Perez is better than Mike Cameron.
Simulating takes thousands of times faster than playing the games. If you want to go through seasons fast, simulate.
In career mode, the system discriminates against pitchers who throw more than three pitches.
Phew, that took a while. My overall review in a nutshell- Buy it, do one franchise and one career, and simulate each of them (unless you're a pitcher in career mode, then play it). The Franchise depth and detail is reason enough to buy the game, but the Career Mode is definitely innovative and also a great mode to play.