Welp...
1. Barry Bonds' plate discipline
2. Alex Rodriguez' power to all fields
3. Andruw Jones' defense (tempted to go Mays here, and I don't just want to pick recent players but strictly defensively, most agree Jones was arguably best ever in terms of reading the bat)
4. Tony Gwynn's contact. Popular opinion says Ted Williams was the greatest hitter ever, but I don't think ANYONE made consistently good contact like Gwynn. He just chose not to swing for power.
5. Cal Ripken's durability. Not something you think about in terms of attributes but if you're going to rate as the perfect player, you've got to be on the field.
Stolen bases are a bit overrated. But I think I created a great power hitter with a great eye and few strikeouts. Elite defense. Very durable.
Now to flip it...
Five attributes for the perfect pitcher?
1. Mariano Rivera's cutter. Nolan Ryan may hold the claim to the best fastball ever, but it's hard for me to judge because he couldn't control it. Rivera threw 1 pitch and everyone knew it. And still they failed.
2. Doc Gooden's curveball. Forget Sandy Koufax. Doc's curveball is the stuff of legend. 12-6 drop and you had NO CHANCE.
3. Randy Johnson's slider.
4. Greg Maddux' control within the zone.
5. Bob Gibson's intimidation.
Edit -- I just realized that I created a pitcher with 3 breaking pitches. And I suppose you'd want a straight fastball to balance it out a bit. But I typed it up already so I'll ride with that. If I was forced to add to/substitute the cutter, I'd go with Roger Clemens' fastball.