I can think of many ways Id rather spend my hard earned gold as on water. You will level a little faster if you kill a MOB only with spells, but consider the costs of the water you will need. Personally, I can spare the extra few seconds per MOB if I at the end can buy myself better equipment. The most cost / time efficient is if you manage the delicate balance of killing MOBS versus Mana regeneration. Questing: Red quests have the highest XP reward. Green the lowest, grey give no experience. Take all available quests in an area to sell FFXI Gil. Read what the quest requires, bundle the quests together. Complete several quests at one time, you can always return them later. Keep levelling or do another quest while you are in the area. Do not return to the NPC who gave you the quest after every single quest, its a waste of time. Consider also if the quest is worth doing. There is a quest from Everlook that requires you to go to UnGoro and Gadgetzan then back to Everlook. The trip takes about 30 minutes, for about 5000 XP.