As examples go, I'd give that C minus. And who is etc etc?
Gabashvili, Haider-Maurer, Ramos-Vinolas, Darcis, B Becker, Schuettler, Smyczek, Phau - can't say any of these have ever blown me away with weight of shot or fierce forehands.
Clearly none are top 20 material (apart from Schuettler with his 45 tournament a year schedule), but presumably by "breaking through" you mean top 100.
Good to hear, sense on this forum at last. I think without having massive talent and big weapons, you can be a steady top 100 or top 50 player. But this means you have to maxmise all the other aspects of your game, fitness, mental toughness.
The opposite, the people with all the talent/weapons in the world, who are top 50 by proxy. But despite this, these guys have no mental strength or will. Examples, tsonga, monfils, Guilbis, the australian who insults peoples girlfriends.
I was stating a truism, not casting aspersions on Broady as I've never studied his game. He's clearly on a learning curve, i.e a work in progress.
All those players you cite, by definition, possess weapons or aspects of play that provide competitive advantage. And it doesn't have to be a bludgeoning forehand or serve either although those are the obvious weapons in today's game. Simon would be a good example with his court craft and tennis IQ.
Broady will do fine if he stays as committed as he has done over the last 18 months, grinding it out in the dog days of last summer in those U.S. ITF tournaments and then pushing on demonstrated promising grit. But if he is going to aggregate those marginal gains ie savvy high level all round skill set with grunt it will take time.
Interesting that super weapons often come with a price, non of the top 4 have the velocity of serve of Isner and Anderson, it's more that they have a broad range of finally tuned weponary unlikely to fail in combat.