Yup, farm map monsters are supposed to be more for XP farming, but the balance is admittedly a bit off. Anyways, we are significantly buffing overall gold gain in the next patch (which will go live sometime today).
When you get stuck on a boss, you can "stack" warrior skill strike by going down to a lower level where you can one-shot them with the strikes. When you think you've accumulated enough, click the auto-advance button(or press P) and the warrior goes crazy with the strikes.
The Aggressive Bartering prestige upgrade doesn't seem to be working correctly for me. The value I see in the upgrade menu changes, but when I have the money I can't buy it, not until I have the amount the original price(without the Aggressive Bartering). Though it does seem the price subtracted is correct, I just wanted to let you know there still is a restriction to actually buy the upgrade.
Healing improves the speed you heal in safe areas, I think, while the speed modifier is dependent on the other skills you have equipped(see "Skill Synergy" on the skill pop-up). The actions that pop up on top are for leveling up a skill to a certain level, ie. 10, 20,30. This increases the synergy % and i believe it also comes with a large Xp Earned boost.
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as of this moment yes