So with legion landing very soon the question of which spec will be the best for this coming tier. We all know that there a large number of sims out there detailing which spec will be best. Currently not taking into account of the level of skill required to play MM over BM this tier MM should be the better spec. However with the creation of mythic+ and the gear which can be obtained from doing them, for a top end raiding guild this gear will be required. With the sims and personally testing within mythic+ BM is the better spec.
With MM and BM using the same stats making it easy to swap between them without requiring two sets of gear, the only problem being artifact power. However with us having 3 weeks from legion launch to normal/heroic EN comes out it provides us with the option of using both specs, currently am a top 50 raider therefore i want to maximum the amount of gear I can obtain before mythic EN gets released.
I proposed the idea of levelling as BM which will make the overall levelling and at 110 make doing the daily world quests easier, while also levelin your MM weapon.-
The main trait within the BM weapon which makes it so nice for mythic+ is "master of beasts" and can be obtained by putting 4625 artifact power into the weapon. After getting this trait starting to put all the artifact power obtained after this point into the MM a weapon therefore getting you ready for raiding. Yes this will mean overall you will have less traits in your MM weapon when mythic EN is released, but as you will have been doing mythic+ to higher level wth your BM weapon your overall level of gear should be better therefore your level of dps will be better than if you had been just putting all your artifact power into your MM weapon.
To note that yes you could still obtained this same level of gear while playing MM even in mythic+ but at the same time putting more weight onto your fellow guildies to carry you.
This is my current plan for legion please post what you think about it and if am complety wrong or not.