People sometimes say that there was nothing to do in Vanilla WoW at level 60 except raiding. This is not true, but I think the reason people believe this is mainly that they don't understand or remember just how different Vanilla WoW was to current WoW. Mainly, there are two points to consider: Firstly, while it's true that the very best gear in the game generally came from raiding, upgrades were gradual and felt rewarding every step of the way, so just improving your gear via quests and dungeons could keep you busy and felt satisfying for quite a long time, even if you never got best in slot. Secondly, many activities that made up endgame in Vanilla still exist in WoW today but just wouldn't be considered endgame because they take little to no time these days.
First off, there's simple questing. I mentioned that I hit 60 in Winterspring, but there were still quests to do there, and I still haven't even been to Silithus except to pick up the flight path there. The last time I played retail WoW, in late Mists of Pandaria, I ran dailies with my pet tank there, and we could knock out a daily hub in five to ten minutes. In light of that, the idea of regular, non-repeatable quests keeping you busy and engaged for long enough to count as "endgame" seems kind of bizarre, but it's true. With combat taking so much longer as well as travel and other obstacles in the way, just working on clearing out your quest log could keep a casual player busy for weeks. At the same time it was worth doing not just to learn more about the world, but also to earn money. In a time when inflation has run rampant in retail, to the point where it's not unusual for people to trade in hundreds of thousands of gold, it's hard to remember a time when every piece of gold was precious and required hard work. Some classes also had interesting and unique class quests to pursue at level 60.
Reputations in Vanilla mainly meant grinding, which I'm not necessarily a fan of, but as one option of many it absolutely has its place. Right now for example I'm working on my reputation with the Timbermaw, which kind of ties in with the first point as I have two quest items in my bags that I won't be able to hand in until I've reached at least neutral with them. It's slow-going and the last time I checked I still needed to kill over 150 furbolgs to reach my goal, but the nice thing about grinding is that you can do as little or as much of it as you like, at any time. Personally I've settled on simply doing one round through the Deadwood camp whenever I'm landing at the nearby Alliance flight point, and I'll get there when I get there.
Both of the above will earn you money as you go along, but it can also be a goal by itself, for example by going out to collect crafting materials which you can then sell on the auction house. Everyone dreams of having an epic mount one day, but a thousand gold was a lot of money in those days and took some work.
I've written about my epic journey to becoming an armorsmith, but of course levelling my blacksmithing hasn't ended there. I'm currently sitting on a skill of 278, and with every skill-up requiring more than twenty thorium bars, it's slow going. However, every single item I craft is actually useful and I can sell it (even if the profit isn't great). I haven't focused on it specifically, but I do mine thorium everywhere I see it and so keep chipping away at that skill bar slowly but surely. Likewise, all the other crafting professions and even the secondary professions all have specific requirements to get them maxed out that aren't as simple as loading up your bags with mats and going AFK at the forge.
Even if you're generally not a PvPer, Alterac Valley weekends are a chance to hop in and engage in some casual PvP even if it's not usually your cup of tea. There are some nice gear rewards to be had, and if your urge for PvE is too strong, there are also PvE quests to be done in the Valley. With the large number of people participating and the battleground being accessible from level 51, it's simply accepted that not everyone will make a meaningful contribution to the actual battle, so feel free to have fun your own way. Personally I was in an AV match today that lasted two hours and 41 minutes (I was there for the entire duration)... let's just say: it was certainly an experience.
And finally... should you be able and willing to take the step up, there were of course the five-man dungeons. While their length made them less casual-friendly than dungeons in WoW are today, even a casual player should be able to make it at least into the occasional dungeon run. Apart from gear there is also a lot to see here: There's Blackrock Depths (which nobody really runs in its entirety in one go, so it will probably take you several runs just to see all the bosses), Scholomance (which has the added complication of requiring a key), Stratholme live and undead, and the three wings of Dire Maul, all asking you to come back repeatedly, not just for gear drops but also to unlock more stories.
5 point review: Justice League Trailer
4 hours ago