Warrior should be a go-to choice for everyone who wants to get into the end game. Protection Warriors in Classic WoW were considered as one of the best tanks, Fury talent build was a great option for DPS while Arms were dominating PvP environment. However, Warriors’ strength relies on the character’s gear, which means that you might need to put some hours into finding the right items for your class. It is also worth mentioning, that Warrior might be one of the hardest classes to level up in World of Warcraft: Classic but rest assured, if you’ll manage to hit the level cap and find suitable gear, Warrior is one of the strongest classes in the game.
Most profitable professions are considered to be Herbalism and Enchanting in pair. You can have Enchanting only for Disenchanting skill, it will bring decent gold. Consider the fact of disenchanting all soulbound armor, not just selling them to a vendor, but I do not recommend to disenchant any kind of weapons, it is more profitable to sell it to a merchant if it is a soulbound item, or sell it on auction house if it is BoE (bind on equip).
If the end game feels miles away, and min-maxing is difficult because frankly, you're gonna take what you get and like it, then the focus of the game changes completely. Suddenly it's about the experience of leveling again, and hanging out with friends, and chatting with people in Goldshire (well, for purely innocent reasons anyway -- the Moon Guard server's Goldshire crew still does plenty of chatting).
And for talent builds. I prefer to make my own talent builds. But I've been playing RPGs since the 8bit days so half the fun is building my own characters up. I already made and bookmarked 1 deep fire mage build, 2 elemental mage builds, and 2 deep frost mage builds. And I might remake them tomorrow if I read up on any good talent choices I left out my 1st 5 times lol. And I have multiple builds for the other classes I play too.