Hey there, I'm Laura Hison and I Live and Breathe New Age Brand Building.
As an answer to your specific question, Company correspondence should be defaulted to email in the digital age. However, the theme of 2014 that will largely catapult Brands to the top is : Personalization and Personalized Options. You can opt to give your clients the choice to receive correspondence via snail mail or email. Most businesses don't want the extra hassle of papers nor do the accountants or other departments. :) However, the fact that you asked is enough to give a substantive tug at the right heart strings and associate your Brand with custom accommodations, which is a goal when launching to premium status. These small things are what matters.
Also, I'd ask if you have defined a USP (Unique Selling Point) in place? This is truly the starting point for Brand Strategy. Everything builds off of that.
Keep in mind, though, what is Valuable and what is perceived as VALUE are two different things whether we're talking B2B or not. Businesses are made up of consumers and consumers equate VALUE with "stuff." Take the American Express Centurion A.K.A. "Black Card" for example. It is a tiny piece of plastic and it costs a pretty penny, or two, to be able to call yourself a Black Card Holder(around 10K the first years for US members).
WHY do people choose to own one? They want the premium status associated with owning it and that status only exists because of the perceived VALUE that it delivers. We as Business folks (talented in a particular craft) perceive value in products or services totally different than a person buying the said products or services. More Stuff= More value = Premium Status. The Black Card comes in a Gigantic Box, a Suave book bag, and uber fancy packaging... with exclusive rewards unlike any other card.
With all that said, there are countless ways for your internet marketing corporation to be the Black Card of digital solutions... and beyond.
The point is personlization, custom options, exclusivity, packaging structure that doesn't seem "packaged" but also promotes loyalty driven, long-term service plans, engagement via personally branded Social Media apps, oh the many choices ;)
In alignment with your vision, a simple app that could allow clients to log in and check reports, metrics, invoices, have access to premium support, and a completely customized and flexible interface is just one way to put the WOW factor in your current Business model.
Operationally, I'd have to know more about your processes and U.S.P to give specific insight.
To wrap up though, the major shift in achieving a Premium Status through Brand Building today vs. the last 20 years lies within culture, empathy and client advocacy rather than the old-school, super professional image achieved by "I'm Bigger, Better, Smarter, Faster, etc" or any track record.
In our digitized world, People are activated and making buying decisions based solely on the intangibles more than ever and this topic will become more important as we become more "digital." So the "HOW" necessary to achieve your goals can be creatively defined once the "Why" is fleshed out in more detail. ;)