I somewhat agree with what you've stated here, but I'm not going to sit and bold each individual statement I like/dislike.
So first, what's the difference between a gen 10 and a gen 50? Aside from the collection of Masterworks that they have to choose from, nothing. What I mean by this is that after a certain point, having heirloom after heirloom no longer grants any benefits on the field. If I have 5 masterworked weapons 3 chest armors light/medium/heavy gloves and a horse, assuming I'm NOT a cav, I can only use three of those ten masterworks at a time. So even though someone is gen 31 and I'm only gen 10, we're both probably wearing the same number of loomed items, at this point, looming more items just allows the individual player more freedom with each gen.
That's what I don't see people focusing on and this is what's been most important when I talk with people on the servers that are gen 10+ like me. The ability to have a repertoire of items to choose from, the ability to go cavalry instead of Two-Hander or Sword and Board with each gen, and be just as effective as you were previously is what we don't want to lose and it's what is most important. Kesh has stated it on the forums as well as Goretooth and I know other people agree with this: It's no mere coincidence that the people who are high gen don't play the game because they're sadistic and enjoy the grind, they play because it's legitimately fun, and part of that fun is not being confined to one build.
People have argued that you can just make an alt if you're tired of your current build. But that's like changing your phone number or creating a new e-mail/aim/yahoo/msn name, you lose contacts. No one knows who the hell you are anymore. This game has a pretty tight knit community and playing on an alt is like playing for your first time, no one knows who the fuck you are. And why should someone have to create a new character when they've put hundreds(literally hundreds) of hours into the one they already have, that's like throwing all of your hard work out the window.
The only way to balance this issue, is to make it easier for the have nots, to have. For example: cutting the total xp needed for every level by 30-50%. So with a 50% reduction it would be 4.35 million xp total to level 31. This would make everyone level twice as fast and making it feel much less "grindy" to lower gen people. This would allow you to keep the 30xp per gen(though I'd suggest 50xp and remove the cap) and probably make everyone happy.
Of course this would increase the total number of heirloomed items in the game, but people can only equip so many loomed items to begin with. There isn't really any point to loom boots or helmets so what you get at high gens (10+) is a bunch of people looming things that they won't always be able to use, things that only increase the players individual versatility and not battlefield effectiveness.
Long story short: I'd rather level fast than have trillions of heirlooms.