There's a trick to the game that I kind of figured out when the game was first released. I dunno if it's how it was intended buuuuut.....it works. Depending on if the game gave you crystals on creation of you account or not, you may be able to do this.
Buy multiples of the item bag from the shop, log into the first map, get the item, then log out. Rinse, lather, repeat, and you can get your character pretty OP to help you with lvling. Just have to be careful not to die and waste all the crystals you just spent lol
And personally, I dump my stats into speed primarily