Arms Warrior Frequently Asked Questions — The War Within (11.1.5)

Yes and no. Ensuring you do not starve so much that you are unable to cast Mortal Strike on cooldown will help maintain consistent damage and the Mastery: Deep Wounds debuff. In practice, this is a minor concern and does not take much in the way of micro-management, but should be kept in mind. With Skyfury and proper talents, it becomes fairly difficult to Rage starve, unless Ignore Pain or Execute are being spammed.

Yes, though not strictly on cooldown. Mortal Strike benefits greatly from Executioner's Precision and, while also maintaining Bloodletting and Deep Wounds. Typically, it will be used at two stacks of either Martial Prowess or Executioner's Precision.

Due to the number of variables involved, the typical answer is to simulate it for better accuracy. Between gear, set bonuses, trinkets, and sometimes even talents, there is no such thing as a one-size-fits-all, though item level is typically a strong indicator due to primary stat being worth much more than in previous expansions.

The only exception to this rule is when a specific fight dictates a certain set of optimal talents and gear pieces that enhance their strength. If you are curious about what kind of setup to go for a specific fight, WarcraftLogs.com's rankings and statistics are a good place to see what others are doing.

We have a guide on how to sim yourself here:

More is better up to a point. Each stat begins to suffer a small amount of diminishing returns upon reaching ~30% (made up of rating, not considering % increases like In for the Kill), which is meant to help players diversify their stats and make more pieces of gear potentially useful, rather than only ever wanting to stack one stat. How much this matters can vary wildly depending on the situation, though, so it is difficult to give a concrete answer that covers all of them. Simulations do account for this, though, so that is typically the best guideline. Generally speaking, Arms will never stop stacking Haste and Critical Strike, though Versatility occasionally pulls ahead when there are multiple or large sources of external damage.