You can use
iZakaroN's SaveEditor (or from
Kiya's site, with description) to redistribute your stat and skill points.
It is also possible to switch character classes (so you would get the warrior's strength damage bonus and special move), though not as easily. If you are not familiar with hex editing, try just using the editor; the game gets easier as it progresses, so even with a bit of a disadvantage using a mage as a warrior, it may not make much practical difference.
Some more hex offsets... (see the
hex teleport topic for a bit of a description on editing the data.000 file).
differences between classes (minor spoilers)
Early Starter Tips (NON-Spoiler Version) (contains much of the information in the above topic)
