As an example, I will take my server values to calculate how many procs you need to make up the price of one Magnetic Mining Pick (40 SS ore, 10 Platinum ore, 15 Expulsoms). Assuming 25g per SS ore, 20g Platinum Ore, and 55x the price of Tidespray linen to craft 1 expulsom in average (got the value from a previous post in this subreddit); 1 Pick is worth 5325g (not counting the elemental flux).
So about half an hour ago we got a post on the PTR Wowhead site talking about new Tools of the Trade questlines being added in 8.1.5. It adds several different questlines that lead to different crafting items for those with max level professions. Some of the more interesting ones, such as Iwen's Enchanting Rod ( look to be REALLY nice to have. This one allows you to gain extra resources for 30 minutes when you're disenchanting items.
The Horde levels 50-60 guide has been rewritten and revamped.  My 1-60 Horde leveling guide is now completely updated for the 1.12 Drums of War patch.  As you can see it is about 15% larger than the 40-50 guide (single largest guide page yet).  There is also a lot of route changes.  I moved the entire Silithus section from level 55 to level 58, which allowed me to include a lot more quests for that zone.  There is also a lot of other improvement to the route, including adding a lot more quests into the guide, mostly from Moonglade, Silithus and Eastern Plaguelands.  This will make the final level 59 grind much shorter.
AddOns (sometimes called addons, add-ons, or mods) are collections of Lua/XML code that augment, modify, or replace World of Warcraft's default user interface. Addons vary greatly in scope and size — they may display information not presented at all by the default UI, add functionality to the default UI (e.g. additional buttons you can press to do things), modify the default UI's appearance (e.g. by changing colors or positions of UI elements) without changing its functionality, or even replace the default UI entirely.
Taking Herbalism and Mining as your two professions can be a lucrative way to level with the very stable and high prices of herbs and ore thus far in BfA. While rested, each mining and herbalism node will award nearly 4,000 experience points which makes it so that four to five herbalism or mining nodes is equivalent to one quest. If you have the Sky Golem mount for herbalism, you can pick herbs without losing mount speed. There are also enchantments for gloves that will increase the speed at which you can process the herbalism and mining nodes. These can be made rather easily by an enchanter and should be relatively inexpensive on the auction house. These enchants will pay for themselves with the time saved while herbing and mining. Remember to continue completing mining and herbalism quests while leveling up to increase the yield of each node making your herbalism and mining leveling experience exponentially more lucrative.
First of all, the value of transmog is decided by rarity and how they look. Some items like Minenarbeithut der Tiefen or Pendel der Verdammnis (they can drop in Uldaman) are worth millions of gold. They are worth so much, because they have a really small chance to drop. Other items are bought well because they look good. Best example in this case is the Glorious set, its legplates Glorreichen Beinplatte reach a 100.000 Gold value easily.