You could say the same about D2's economy - it became about MFing (magic finding) for loot that you could trade in for the equivalent market value in item currencies: Stone of Jordan rings, or later, charms and points on a 3rd party forum (forgot the name). Then, you could buy the specific piece of shiny loot that you want for your character's build.
That, or you farm and hope that the piece of loot that you want serendipitously drops.
Barbarian is stupidly powerful, at least in normal. I killed Diablo first attempt, no AH bought gear (I hate the AH, think it ruins the game, and haven't bought a single item from it). I stood toe to toe most of the fight using the first passive ability and two other survival related abilities.
It's funny there's a lot of whining about melee classes being weak and I just don't see it (I'm only halfway through nightmare) -- I'm playing a monk with my wife's wizard and the monk is just as ridiculously overpowered as the barbarian (as in run to the biggest concentration of mobs and make them explode). Demon Hunters have to deal with enemies that are immune to missiles, which is ridiculous. (The worst thing with melee so far is dealing with flies in Act II.)
As for the challenge level of normal, I think it's fine for new players. I just wish nightmare were unlocked to start with (with whatever mechanics you like). I don't like games to assume every player has played twenty similar games and knows how to finesse gear, specs, etc. I imagine normal is quite challenging for new players (and I had trouble with two bosses on my DH and one on my Barbarian -- mostly because I had gotten so far using simple minded tactics and actually had to think).
Yeah, wait until you get on inferno... All mobs are basically immune to your pulls/pushes/whatever, and you can't really tank. And you're not very good at kiting either, being melee.
Forget about not using the AH in inferno, a barbarian pretty much needs gear farmed in act4 to progress.
I'm halfway through inferno on my DH and haven't met a missile immune mob yet. I think some of them have damage reduction for missiles, but I still dps them down easily. The hard mobs are the ones with invulnerable minions/fast.
You could easily beast D2 on hell difficulty without resorting to that, google for "d2 build hell cheap"
See: fishymancer, summonmancer, lightning sorc, windy druid, any barb, etc.
And yes, in D3 you cannot progress past inferno a2 without ah gear or exploit farming (goblins)
That, or you farm and hope that the piece of loot that you want serendipitously drops.