Fast Level Up:
There are three items in this game that will allow you to gain levels at an
Learning Ring: Increases EXP by 30%.
Coin of Fortune: Increases EXP by 50%.
Book of Refining Gold: Turns each Monster into at least 10 Mystic Gems.
So, from this you can see that if you have a
character equipped with 2 Learning Rings and a Coin of Fortune they will be
getting roughly double the rate of experience that everyone else is. This will
allow you to get a Character like Valkyrie to the high levels up fast.
Fast Materialize Points:
Get into the game until you reach Chapter 4. When you get the weapon The Living
Spear: "Crimson Edge", you can sell each of them for 6000 MPs. During
the later stages of the game you probably will have 12-15 of these. That adds up
to at least 100000 MP that you didn't have before.