Your time is partyl short because of the leveling/money cheats, even then you probably only shaved a few hours at best but now you can replay the game and get the extra endings, most of the cast get a special ending associated with them or their time period. Also, you can get a different ending if you use the Epoch to travel to 1999 A.D. and you get a different ending if you try to beat the game without resurrecting Crono. If you kill Magus instead of letting him join you, then Frog reverts to his human form in all of the endings that involve the Epoch.

Glad you enjoyed the game but now you should do the new sidequests with the abnormal time portals so you can get the lowdown about Chrono Cross and the truth about Magus, Schala's fate, and Porre's uprising.