Grandia

Until, at the very least, you get through New Parm, explore the towns and non-dungeon locations you find yourself in THOROUGHLY. Not only are the NPC conversations usually worth your while for hilarity, there are plenty of little sidequests and what not you can do to get yourself some pretty decent items (and in one case, a very rare item that will be useful at end game - check the below spoiler for details).

Once on the Steamer, in the 2nd class cabin (the one with all the people and shops), there is a older man, whom you will find out is stowing away. Talk to him each and every day on the Steamer, and once you leave the Steamer, look for a moving barrel. "Talk" to it, and the man will give you (IIRC) a Miracle or Golden Potion, which is a very rare high-end restorative. Stash it immediately for use WAAAAY later on.

Unless you explore EVERY SINGLE PART of EVERY SINGLE DUNGEON (or use a guide), avoid giving Mana Eggs to Sue, as she will not be in your party come around 3/4ths of the way through disc 1. . Note that if you do give her Mana Eggs, there will be Coloring Books for each element you gave her that grant around 1/3rd of her experience in that element to whoever you use it on, just like her weapon books .

Get Justin Earth and Fire magic as soon as possible, and level them up to around lv10. Also, level up his sword to around lv15 by the time Gadwin leaves the party. Why? Dragon. Motherfucking. Cut. Although it's pricey, it will basically rape just about any regular enemy you encounter for the rest of the game, until you get Heaven & Earth Cut .

Remember to buy a massive stockpile of power mushrooms when they come up if you're at all interested in them. There are also enough mana eggs to make sure your endgame team has every element if you feel they need them, but take it easy on the non-permanent party members if you're not in the mood to hunt all the eggs down. Also keep weapons that can be used as items like a hail bow and the wrecking axe if you want to cut down on even more grinding.

You will want to hunt down those alligator (maybe called chameleon) looking things that teleport all over the place when they see you. There are two types in forest areas and they probably give you full experience for magic and weapons to 99. Be sure to leave the area and come back to make them respawn.