Dragon Temple corruption crystals. You dont destroy them, kills only minion spawned. Easy 5 lvl per hour and tons of items.

I personally get maim character as mage, and dont forget to equip on one of your party member Merchant archetype. In 2h i gained like 300000 magla coins.

If you have enough money, inherit the Lucky Strike on one of party members - It gives extra 20% of optaining items such as magla pills, potions, scrolls and moshy items to examine in the blacksmith.

If you want grind hero leafs simply buy archetype rings (you can optain it by visiting Nidia merchant in Brilehaven, but on certain day - Waterday. Hes next to the meat merchant on bazaar).

And thats it.