Barbs in particular actually DO get to the point where they can handle those packs just fine. Its just that the gear hump is steep for them, but once they are there, they can handle them just fine. I mean, your not going to convince any of us otherwise. We have all be playing since release and or beta, and we have all watched Kripp eat Act 3 inferno alive while his DH friend was in the game, but back in town repairing because even with his 100k dps, he still gets one shot.
Once the melee clear that gear hurdle they have one hell of a fun ride. DH will always be "killing a pack after a hand full of deaths" no matter what unless Blizzard changes something. Sounds a whole lot like you just have some bad class envy. The hurdle for melee in Nightmare is not insurmountable and its not impossible for melee. Stop it with that.
Lol at referencing Kripp, the guy who had his team spoonfeed him gear from exploiting resplendent chests and pre-nerf ghosts and also received godly gear for extremely cheap (31% block Stormshield for 6 mil? Good luck finding a deal like that now). Once again, the issue is not that it's impossible for melee -- of course it'll be easy enough with the best gear, you can say that for anyone -- it's that the Barb or Monk requires FAR better gear than a range hero to even come close to viable. How is someone who decides to start as a Barb or Monk supposed to overcome the gear hurdle exactly?
Roll a DH to farm with?
That's terrible game design. And when did I say anything about Nightmare? Is that where you're stuck? This is about Inferno. And ONCE AGAIN, it is not about the impossibility of Inferno, it is the CLEAR advantage of range over melee in terms of survivability (DHs have, at the very least, 6 seconds of invulnerability with SS WHILE being able to fight from range) AND raw DPS (you said yourself that you have over 50k DPS without Sharpshooter. Kripp has less than 15k DPS with over 30 mil~ worth in gear).
Compare the amount of DHs and Wizards who have made it to A4 with the amount of Monks and Barbs who have even gotten through the beginning of A3. I guarantee that the range blow the melee out of the water. Oh yeah, don't forget that all the DHs and Wizards farming A3 Siegebreaker and chests + A4 are putting up melee weapons with life on hit and str/vit/all res gear for gazillions of gold, well out of reach for the majority of melee-only players.
The point of a game is to have fun, and if to have fun I either a.) have to roll a DH or Wizard, classes I don't enjoy, to farm gear for my Barb and Monk, JUST so they can be kinda-sorta viable in A3 and beyond; or b.) wait for the RMAH to come out, then this game sucks.
FYI I have a 2H barb making his way through A3. That's after I rolled both a Demon Hunter and a Witch Doctor to farm gear for him. Great game design there.
Honestly WD are the closest to us but they deal with things a little differently with the pets.
WD pets are trash and any WD in Inferno will tell you that. Using pets in Inferno (with the exception of fetish dudes -- which aren't even really a pet) is a great way to waste a skill slot.