@Erloas: How do you define "get any farther?" That's what I don't understand. The whole point of this model is that you choose your own endgame. If GR100 is your goal, then it should be expected that only a handful of builds are capable of getting there. If 70 is your goal, there's a large pile that can, and plenty of room for experimentation including with existing builds.That many of those can't get to 100 doesn't make them worthless.

If you're sticking exclusively with the handful of builds on Icy-Veins, those folks (who by the way get all their builds from one guy and his preferences) don't even care about a build unless it can clear 80 minimum (85 for LoN), and even then they limit themselves to 1-2 per set. That doesn't mean other builds aren't out there, nor that you can't tweak the ones they've come up with to suit your playstyle. Jackal said his endgame was 70 to unlock Primals, and there are many more builds out there that can do that than he seems to be aware of. I probably could make a 70-capable Corpse Spiders build if I really wanted to.

As for the classes feeling the same, I'm just not seeing it. Even for the broad archetypes you mentioned like "run-and-gun", they feel very different. A whirlwind barb,charge barb, jade WD, dashing strike monk, thornsader and flashfire wizard are all "run-and-gun" but they feel very different from one another in play.