Far ahead of it's time, Soul Calibur was graceful and perfectly balanced. Even after two sequels, it's still fun today.
The thing that makes Soul Calibur so great it that all of its characters are so well balanced without being similar. They all have their own weapon and style, and each one has an easy to learn momentum, so playing as a new character is easy after a few tries. When I say that they each have their own momentum, I mean it to say that using the analog stick along with a corresponding vertical or horozontal attack will use the weapon in a way that feels natrual. For example Y (vertical attack) and up with Seigfried's massive sword will have him slash upward and change stances, where you can then make your next move, either be the sweep the sword foward, or slam it back to the ground with heavy force. One of Mitsurugi's horozontal attacks will have him pull back when you tug back onto the analong stick and lunge foward when you choose so. There's a different character vs. character strategy for every matchup, and each one is evenly balanced.
The gameplay was so far ahead of anything around around the time. The sequels only improved upon it, but Soul Calibur remains still a great game to go back to. They really put an emphasis on timing and grace, as opposed to mashing in combos. Never does the game feel broken or chalked up with fake difficulty. Soul Calibur carries itself as the only thinking man's fighting game. Patience, timing, and strategizing are the best techniques to use to win.
Soul Calibur is best played against another person, but you can only do it locally. Since the original never had the feature to do so, I won't mark down points for not including online. I do say that the value is somewhat diminished from not including all the modes and unlocking everything from the beginning. This doesn't however, take away from the sheer quality of the story mode and verus play.
If you've never played Soul Calibur, it's worth it to check out, especially with 4 around the corner, (to see the series' roots) but also because it's still legitimately fun.