Alexis Petridis writes a superb column for the Guardian about the steps that musicians have to take before releasing a major label record. It's not just about the music, it's about branding, and fashion, and all of the other subconscious hooks that tell your audience that you're meant for them.
When you've been growing your audience organically over time, you will probably evolve a lot of these same ideas on your own. In fact, even the most stylized acts (Petridis cites Keane as an example) seem to have a look-and-feel about everything that they do that really fits.
The bigger question is: Why do we feel it's inauthentic to seek out help when connecting with an audience? Keane spent some serious money to go through a six month branding process that probably allowed them to connect with a mass audience about 3-5 years sooner than they would have if they were grinding it out (like you probably are).
Was it worth it for them to take the shortcut? That depends, in my opinion, in what they paid. And as much as industry insiders and Pitchfork readers might grouse about the success of a band like Keane, the numbers on the tote board tell the story.
Whenever you're working with any consultant, vendor, or service provider, weigh the opportunity cost of how much of your time (if you paid yourself hourly) you'd save by simply paying someone. In many, many cases, the hired gun gets you to your goal sooner.