There's another factor as well: In spite of the added content the PS2 version is said to have horrible load-times that simply did not exist in the Gamecube version of Symphonia. I haven't played it myself so I can't really say, but -theoretically- you should be able to get around that by running the game from the harddrive (if you're using an older PS2 and not using a USB HDD, that is).
The load times aren't that big of a deal with using USB Loader to run the game off the harddrive.
The big issue is that the battles are 30FPS instead of 60FPS like the Gamecube version...so sloowwww, the additional content isn't worth it with the performance drop. So it's not surprising people aren't hard at work trying to get variable-width fonts working on it, it really isn't worth the effort for such a subpar port.