I've leveled around 10 characters from 1-60, 6 of those during the actual Vanilla age, and 4 of those on private realms, and with that experience under my belt I often see a lot of false information being represented on account of the vanilla "experience".
- You do not have to grind at any point between 1-60.
If you know where all the questing hubs are, there are efficient paths that can take you from the moment you zone in to your new character, all the way to 60 without even so much as thinking about grinding. It's definitely not nearly as direct and guided as modern day WoW is, it takes some research on knowing which hubs are optimal for your level window, but it's not that difficult.
However, grinding is an option for those who don't like questing. Compared to now, mob grinding an entire level was actually feasible and doable if you could bare the repetition of grinding mobs for hours. It is a popular leveling strategy for mages, especially when they reach the plaguelands as they can just AOE undead mobs down for hours and make huge xp.
Now, to be fair, this depends on what patch the server will be at on release. If they do some kind of thing where they recreate how it actually was from patch to patch, this won't be true, as the base version of WoW did have some difficult XP gaps to grind through. The "final" version of vanilla, however, did not.
- The consumable grind for hardcore raiders is not that bad.
I see a lot of people who incessantly say that vanilla is just too grindy because of consumable farming for raids. This is simply not true for a number of a reasons.
Firstly, any guild worth their salt has a broad range of professions, both gatherers and crafters. Usually materials are compiled in to the guild bank to make consumables to be doled out. Often you may be responsible for providing your own flasks or DPS elixir, which are typically not very expensive, but it is very common for guilds to provide their raid with any extraneous consumables necessary like resistance and protection potions. The only consumables that you will likely feel pressured to farm for on your own time (other than gold for the others) is the Jujus, Winterfall Firewaters (melee), and oils (casters).
Resistance pots, Flasks, and elixirs are typically widespread and readily available either from your resident alchemist, or the AH.
This stereotype of farming being excessive for vanilla players stems from the hardcore guilds who absolutely needed to farm ridiculous amounts of consumables during their race through AQ40/Naxx40. They were playing excessive amounts of hours pushing this content, and the number of wipes are in the hundreds on many bosses. It took weeks to down 4 horsemen, for example, not even the final boss.
This will not affect a vast majority of people on the classic server who stick to a steady raid schedule, even in Naxx, because you have plenty of off-raid time to bank up a small bit of gold to buy your necessary consumables for raid night.
- Classes deemed "useless" actually are not not as bad as the stereotypes say.
Shadow priests. Ret Paladins. Sub or Assassin Rogues. Arms Wars. The list goes on. There are many specs that are deemed to be completely useless in the face of a more optimal choice for said class.
There are a heavy number of factors in to what decided the "uselessness" of certain classes in vanilla, and it strongly depends on how Blizzard decides do their server.
For example, many specs were outcasted due to the debuff limit. When the debuff limit is capped at 8 or less, it forced guilds to think about the debuffs they put on bosses. That means, when all the debuffs are thrown in to a pot, arms warriors come up short compared to the other options. Since arms warrior debuffs are essential to maximizing their damage, this in-turn made arms warriors less desireable to fury. The same can be said for hemo rogues (hemo, rupture), and shadow priests (plague and flay), and Ret Paladins (judgment of the crusader).
If they cap the debuffs low, you will again see this sort of favoring, of course. However, later in vanilla they increased the cap to the point where this sort of thing wasn't as important, but at that point in the game the stereotypes were locked in.
However, if you go to any vanilla players or even just look at a certain private server's public dps logs (basically, vanilla servers have their own "warcraft logs" sites that works very similarly to the one you might use in Legion, though obviously with less boastful features but the important stuff is there), you can find very empirical evidence of players playing a lot of these "lesser path traveled" classes to surprising competence. We've seen Ret Paladins crushing meters in MC all the way up through Naxx, we've seen Shadow priests doing the same, and we've seen all 3 specs of rogue put out competitive DPS with combat. I have personally experimented with hemo in vanilla to surprising success with proper gearing, as long as my debuff wasn't minded, competing in damage with other similarly geared combat rogues in BiS gear.
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Many new things have been 'discovered' in the golden age of vanilla private servers, and I would not be surprised to see a lot of old vanilla players who skipped the private scene be shocked that what they thought was an absolute in vanilla, really wasn't so absolute. It mostly comes down to gearing. A lot of the lesser liked classes for raiding performance tend to be more reliant on gear. This means that they require some base epic-level pieces to push over some thresholds before they are brought up to the same potential as more elementary dps classes that do not require such simply due to balance quirks. It's kind of like some of the secondary stat "soft caps" a lot of classes have in Legion, where before said cap it feels like the class plays like crud, and then once you hit the threshold, you feel godly.
In short? : If you want to play a spec considered "garbage" in raiding, it might be difficult due to the stereotype to find a guild that will fill a slot with you, but if you're passionate about giving it a go, most of the time there are guilds out there that aren't hyper-concerned with 1 slot going to a ret paladin or a shadow priest, but be ready to fight the stereotype, which means studying your class mechanics, and be hyper-attentive to your gearing and stats, because if you put in the work, you can be competitive, it just takes a bit more effort off the start.
And these are the 3, I think, most often mis-represented things about vanilla today. Feel free to discuss, disagree, or add anything you believe are strong misconceptions about daily vanilla life. Thank you.