To have a good charcter you will need the perfect stats. Here are some hints as to what they should be for best results.
For the mage it would be best to not raise MP unless your Improving Max MP is to it's mastery level. Instead you should have three luck ahead of your level and everything else on intelligence. By doing this you can wear the armor for mages and you will do a lot of damage when using magic attacks.
For the archer you should have five strength ahead of your current level and everything else on dex. The bows need some strength required to use them that's why you need strength. Also by having tons of dexterity you will be able to hit strong monsters becuase your accuracy is high. Do not ever raise HP or MP.
For the warrior you need both dexterity and strength. I have come up with a way of formulating the stats so that I am both strong and accurate. By the time you leave Maple Island try to have about 40 strength and 20 dexterity. Then for every five levels raise your dexterity by a total of five and your strength by a total of 20. When you are level 15 you should have about 60 strength and 25 dex. By doing this you can still hit the monsters that are about your level. Also do not raise MP or HP unless Improving Max HP is maxed out.
For the theif you should have your dexterity twice your level plus an additional one stat point. Use everything else on luck. By doing this you can use all the daggers and you can dish out a lot of damage with them. The reason you need twice your dexterity plus one is because some daggers are (for example) level 17 that requires 35 dexterity. If you use stars then you should just have dexterity twice your level.
Thank you for considering your time for reading this. I hope it was useful for making good characters.

P.S. When rolling the dice to get stat points, try to get the two stats that you don't use at four. Then you have higher of the stats you need.