You’ll be the main target, as a rogue, on a pvp server, out of stealth, engaging mobs. If you want to farm open world, do not roll on a pvp server. Especially the cancer that is Firemaw. You will regret it.
There’s no single place except Silithus’ Hives (Thorium Veins) on Firemaw which I would recommend to aim for farming.
This server is crowded of bored bis toons aiming to ruin other peoples day.
of course you roll mage if you want to play world of warcraft as single player game when needed.
Things you can do with mage
1- Solo Gnomeregan farm with 300+ mobs in 1 pull
2- Solo Scarlet Monastary Cathedral + Library + Arms farm with 1 pull
3- Solo Maraudon farm 320 pull, 360pull, 400 pull, 420 pull, 480 pull, 500 pull, 500 pull + princess
4- Solo Stockades farm with 2-3 pull
5- Solo BRD farm
6- Solo stratholme farm
7- So many other dungeons and also open world farm opportunities.
You can outplay any PvE content as mage in classic, you can also PvP in the future, you can find a lot of educational videos on youtube about what is mentioned above.
Solo PvE farming as a rogue is nice. I have a 60 warrior and a 60 rogue, for outside PvE killing I usually go with the warrior, for dungeons and tricky “mining/herbing” I go with the rogue. These two classes are fun for the more slow paced farming that I think that you are looking for.
As said by another player, if you care about being the fastest/most gold per hour, you should look at the mage who is the king of classic gold farm.
I find the rogue is VERY good for herbing/mining. For mob farming, probably want either a plate wearer or a hunter.
Rogue with sap + blind (blind can be used to stay out of combat if it’s timed well, works on pretty much everything but named elites) can get to pretty much anything node wise.