Update: Found an error in my model. Crit is worth a little more then I previously stated. It has been updated.
Ahhhh. Remember the good old days in BC when the moonkin Rotation consisted of Moonfire and casting Starfire 4 or 5 times. That was when theorycrafting was easy. If you figure out how each stat affects each spell you can come up with a good estimate of how much each stat is worth realtively quickly.
That is all ancient history with the introduction of Eclipse, new set bonuses and Glyphs. If you look around the various forums you will see a lot of people saying how much each stat is worth and all the different versions are not as close as they used to be. As a result, I have built a new model to try and determine the value of each of DPS stats for a Lunar Rotation. Well, the results are in.
I'm going to do this post a little bit backwards then I normally do. I'm going to talk about each of the stats and give my results first. Then I'm going to talk about how I got the results in the end.
First off all, these results are for a perfect Lunar rotation with no lag, and no movement on a single target. I have also excluded both Force of Nature and Starfall from the analysis, and the results are based purely on DPS. Also, these stats are based upon a pre-3.1 BiS gear set with 4T7 set bonuses. I expect these numbers to change as our gear improves since our SP will go way up and our Crit and Haste will stay realtively the same. I will redo this analysis after we know more about what a BIS 3.1 Moonkin looks like.
The results aren't all that shocking. The values I came up with still fall into the standard Hit > Spell Power > Haste > Crit explanation.
Hit Rating: Relative Value = 1.54 - Hit Rating has the highest per point value of all the DPS stats assuming you are below the hit cap. This valuation just shows you how important it is to be hit capped. In my opinion, all raiding Moonkin should have the talents of Balance of Power and Improved Faerie Fire. This means we need to pickup an additional 10% hit chance from gear and other buffs to be hit capped.
So, what is the hit cap? 263 for Tauren and Night Elves with out a Draenei in their party. 236 for Night Elves with a Draenei in their party.
Spell Power: Relative Value = 1.00 - Spell Power is the standard by which all other stats are measured. After you are hit capped, Spell Power is the best DPS Stat on a point for point basis. This is why, it is always recommended to use Spell Power gems and food when possible.
Haste Rating: Relative Value = 0.80 - This is where the debate usually begins. Haste Rating is a great DPS stat the makes your spells cast faster and lowers the global cooldown. The down side to Haste Rating is that it also makes you consume mana faster and if you have mana issues the Haste will make them worse. Also, spells with short cast times like Wrath and the DoTs can reach the minimum global cooldown fairly easily with reasonable amounts of Haste Rating. You can find my post on the Haste Cap here.
Crit Rating: Relative Value = 0.62 - Crit Rating is the least valuable of the "pure" DPS stats, but that doesn't mean it isn't a good stat. Crit Rating also has the side benefit of helping you to generate mana using the Mana on Crit mechanic.
There are two important things to remember about crit. The first is that even though you don't want to necessarily stack Crit Rating, you don't want to completely avoid it either. The second is that you get a lot of Crit Chance from other Sources like talents and raid buffs. This is the main reason why Crit Rating is ranked so low.
Spirit: Relative Value = 0.34 - In patch 3.1.2, Improved Moonkin Form is being buffed so that your Spell Power will be increased by 30% (up from 15%) of your Spirit. Also, Spirit will help you regen mana if you have the talent Intensity.
As a general rule Spirit is a stat to be avoided, because Haste Rating and Crit Rating are so much better in terms of DPS. However, Spirit is becoming more and more unavoidable. Most caster items now have Spirit, and majority of the ones that don't have Hit Rating. It is fine to have spirit on your gear, but never intentionally stack it.
Intellect: Relative Value = 0.35 - Intellect is not a good stat in terms of DPS but it is almost completely unavoidable. Virtually all caster items have some amount of Intellect on them. Intellect has a lot of side benefits though in Mana Regen since it impacts all of our major mana regen talents. You will pick up enough Intellect just by making commonsense gear choices, therefore you should never intentionally stack Int.
(Edit: I updated the Spirit and Int numbers to take into account Stat Multipliers like Blessing of Kings. Thanks to Antonetz for pointing this out.)
Other Stats: Relative Value = 0.00 - All other stats have very little direct impact on your DPS. Stamina is the only other stat that you need in any significant quantity, but you should pick up plenty making normal gearing choices. Mp5 can also be helpful if you have mana issues. However, most moonkin don't have big mana issues that can't be solved with talents. Avoid Mp5 if possible. Spell Penetration and Resilience are useless in a PvE environment and should be avoided.
Hit = 1.54, SP = 1.00, Haste = 0.80, Crit = 0.62, Spirit = 0.34, Int = 0.35
If you want to look at the model and check my work you can find it here. However, I want you to keep a few things in mind. 1. It is a very large file. Download at your own risk. 2. It does have a couple of macros on it but you don't have to enable them for the spreadsheet to work. 3. This is NOT a tool to help you model your DPS. If you want something like that go check out WrathCalcs. 4. In conjunction with #3, it is not userfriendly. It even confuses me and I built the damn thing.
How it Works: I built the model to choose which spell to cast based on the current situation. It uses the random number generator to determine crits, misses, and procs. The model assumes the linked Talent/Glyph build. The model assumes the following Cast priority:
1. If FF is not up, cast FF.
2. If IS is not up, cast IS.
3. If MF is not up, cast MF.
4. If Eclipse is not on cooldown, cast Wrath.
5. If Eclipse is on cooldown, cast SF.
This means that FF and the DoTs will be refreshed during Eclipse. I won't go into detail about it now, but I now think this will give you better DPS then weighting for Eclipse to run out.
The model uses a 60,000 cast sequence. This is equivalent to about 26 hours of continuous casting. This may seem like overkill but I wanted to smooth out as much of the randomness as I could.
Using base stats of 2900 spell power, 41% crit chance, 16.5% haste from gear, and 100% hit chance, I ran the model 1,000 times to find the average total damage, average total cast time, and average DPS for a control group. I then adjusted each of the stats by significant amounts and reran the model another 1,000 times for each adjustment to see how the DPS changed.
The adjustments were made in significant amounts and then averaged to a per point value. For example, to find the value of Spell Power, I increased the spell power used by 50 to 2950. This resulted in an average increase of 61.81 DPS or 1.24 DPS per point average. To evaluate Crit and Haste I increased both by 1%. To evaluate Hit Rating I decreased hit chance by 1%.
The stats where then weighted relative to each other, with Spell Power being the standard. These new values will be applied to my gear ranking and I hope to have it updated soon.
Whats Next: I am kind of excited about what I can do with this model. I plan to create additional models to evaluate a solar rotation. I would also like to add lag into the model to see the impact. I would also like to build a model that takes movement into account if possible. Finally I will be using the model to evaluate new set bonuses, glyphs and talents.