Usually it's best to avoid a lot of instance runs. It is too difficult to account for bad groups, and some instances are too far away with too few quests. Since the experience is very good, it's a good idea to clear nearby instances which have a lot of quests once (Gnomeregan, Deadmines for Alliance). Distant instances with few quests should be avoided (Deadmines for Horde). Low level instances can be cleared by paying or befriending a single high level character. However, since patch 3.3 a new Dungeon group finding system has been implemented, as well as a direct port to dungeons (when entering the group you get ported to the dungeon and back to the same location if you leave it) and thus the travel time to dungeons has been greatly reduced. This makes it a good idea to complete quests or grind while you wait for a group to become available.
With 8.0, Blizzard introduced World of Warcraft’s second ever stat squish — where all the numbers in the game are lowered across the board for clarity. While it may make the game easier to read, it has caused some serious in-game problems. Since the patch, Blizzard has been throwing out hotfixes each day, fixing things that the stat squish either forgot to alter or simply broke.
As you're leveling, I generally recommend you just follow the natural flow of the progression through each zone. They're laid out fairly reasonably. But don't be afraid to hop around, especially if you're near a quest objective. You shouldn't actually need ALL of the zones listed to reach 62. Pick the ones you like best. It's much more important to simply be as focused as possible and flow from one quest to the next.
Pick druid, paladin or monk. Get heirlooms if you can. Grind mobs until level 5 - 6. Start doing the easy "just kill these mobs outside town" quests until 15. Queue rdf as every role and do every dungeon you can (with heirlooms you could probably solo the dungeons) while you travel to higher lever zones. Keep doing the simplest quests while you're waiting for rdf (which shouldn't be long). I leveled a druid to 100 once doing this in maybe a day /played, but he was also rested for most of the process.
That means, if real players value their time at least as much as gold-sellers value a bot’s time, tokens should never be as cheap as illegal gold. But if it becomes as cheap to buy gold from other players than it is to buy it from gold-sellers, the players who patronize illegal services will switch to tokens. That means more tokens in the market, and therefore, lower prices, so the gold-seller price should impose a ceiling on WoW Token prices.
World of Warcraft Gold (US) is a currency used in the US server as a medium of trade. WoW Gold, items are rewarded after killing the enemies. WoW gold is a limited resource and is hard to come by even though gold can be earned by various ways. It is still time intensive for any player to gather the gold needed to get better gears which make advancing easier. Because of the enormous need for WoW Gold, it has attracted many exploiters such as dupers and gold farmers. Arguing that they ruin other people's experience and enjoyment of the game, Blizzard has put up a strong fight to combat these exploiters by banning large number of accounts involved in the activities. However, there are as many players who would not want to invest their time and are willing to pay the extra money to get through the game. Generally, the price of WoW Gold in the EU servers are more expensive than those in the US.
In 2015, Blizzard started letting players buy gold from each other using WoW Tokens, to try to control the process and mitigate damage. “Time is money, friend — but sometimes one is harder to come by than the other,” Blizzard says on the official page. “Now World of Warcraft players can use the WoW Token in exchange for game time or Battle.net Balance!”