Getting good gear by farming in D2 was almost impossible, you had to either buy it, bot for it or be a godlike trader.
This is pretty much only true if you believe that you need enigmas, sojs, shakos, verdungos and some other crazy items to achieve your goal. It might only hold true if your desired endgame is PvP (and even there I'd assume that build choice will trounce the necessity for lucrative riches), but if your endgame is to reach Hell, get high-leveled, kill the Ubers, etc., every class had a build that you could complete with items for a few Perfect Gems.
All ranged casters only needed +skills to prevail - and that category includes some classic, no-brainer, killer builds like dual-element Sorceress (Act 2 Drognan on Normal difficulty can be shopped for a +3/+3 staff socketable with little trouble, mana problems are easily dealt with by just quaffing a lot, and overall, you only need +skill items which should be abundant; amulets that give +skills are common and often drop with +life and +mana), Lightning Javelin Amazon (can wreak havoc with a Cracked Javelin, but Titan's Revenge, the ultimate Java weapon, is a fairly common artifact that drops as early as normal Baal), Lightning / Death Sentry Trap Assassin, Cold Elemental Druid, and, finally, everyone's "favourite", Blessed Hammer Paladin.
Summoner Necromancer is in his own special category because he can beat the game naked by judicious use of curses and careful play while having 20 skels do his work and just Corpse Exploding the whole map for a massive, area-clearing chain reaction. Summoner Necro's self-reliance make MF% items great on him, because no matter what you give him, proper play will prevail anyway. Summoner Necro can be a great MFer in Hardcore mode. You can even play the ever-so-giggle-inducing Boner Nec and simply generate Corpse Explosion fodder using your Bone Spear.
It wasn't perfect - physical damage dealers were really weapon-reliant, so you really did have to farm up a bit for those. Not to mention the requirements for Attack Rating, Defense, and higher HP pools than non-martials. You can still make a melee that's exempt from this problem - just give him a massive, naturally high damaging ability (Paladin's Holy Shock/Freeze, Fireclaws Werebear Druid, Berserker Barbarian, Phoenix Striker Assassin), some Crushing Blow against Immunes to their respective elements (super common on Exceptional and Elite items, and you can craft gloves that increase this statistic as well), and pump their Attack Speed high.
My Fireclaws Werebear used a crappy, shopped dagger that only gave +40% to IAS and erased Nightmare with it without dying once. In Hell, the era of Fire Immunes did screw up his killing speed, but then I found a Baranar's Star - not a crazily difficult thing to find. In a party environment, which I sometimes played in, I was still relevant with just spamming the extremely strong AoE stun on Shockwave, and, of course, all that had no fire resistance still got pummeled to bits. Even if you had no luck whatsoever, you can find a white Phase Blade and forge 6 sockets in it at Larzuk's, which is guaranteed, and just stack it with Shaels (just run some Countess for that). Some Normal and Nightmare-tier items, like Bonesnap, Ribcracker, or Butcher's Pupil, can be upgraded at a modest price to retain relevancy way into Hell difficulty. The above is true for pretty much any elemental-reliant melee.
But even pure physical damage dealers can be made cheaply - they might be a bit of a pain to run untwinked, but they will work. Just stack Crushing Blow. A very cheap build specifically designed to clear Uber Tristram is a Smite Paladin who uses Normal difficulty-tier crap like Goblin Toe for equipment - stuff that a permanent Mephisto/WSK/CS/area85 runner just vendors instantly at Charsi's is gold to someone who is just starting out. But good items for physical damage dealers are more common than you'd think, still, and there's a lot of tricks to help you.
Nevertheless, every class has a build that can complete the whole game without bonus farming at all (just full-clearing everything), and can even do that without completely murdering their killspeed. Note that many builds also exist whose endgame isn't to fullclear the game at all - Blizzard Sorceresses are often made solely for stacking Magic Find, and they do not have to progress beyond Act 3 Hell, so that they can endlessly spam Mephisto/Ancient Tunnels/Andariel/Countess. Some people make oddball builds solely to cruise through Nightmare and park their character in Hell - one guy, back in D2Classic days, completed a Firebolt Sorceress hardcore run on Nightmare and ran some bonus restrictions on top of only ever using unsynergized Firebolt and Warmth.
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With all that in mind, I'm kinda considering if I should get into Diablo 3 or Path of Exile, because I like the genre and don't mind Good For What It Is, and the social aspect manages to usually increase enjoyment from playing subpar games. It's mostly that D3 is still horrifyingly expensive.