Considering the past, present and future, your last couple of sentences allude to what separates the little frogs from the big frogs in this pond we call expedited freight. For Ex1 (or any other company) to broaden and diversify their customer base they need a comprehensive marketing plan and an experienced and knowledgeable sales force to impliment it. The company needs this representation established geographically, with salesmen in territories sized so they can be effectively worked and their accounts are seen on a regular basis. Express 1 has this in place - and they are capitalized well enough to support this marketing structure. Additional business can sometimes be brought on quickly in significant amounts if contracts are signed with the right shippers. The problem with market segments like Temp. Control and DOD is having the drivers and equipment IN PLACE when the business goes active. When getting started with these types of customers who are usually extremely demanding, this carrier needs to have Ex1 trucks available in the right places; the customer will almost never accept partner carriers, especially when just getting started with a new expediter.
Based on the feedback I get from people who work for them, my guess is Ex1 is positioned to continue their expansion and growth on a national scale because they've become a truly national carrier with the fleet size, marketing plan and sales force necessary to carry out their plans. These are things that drivers should ask any carrier's recruiters about whenever they get down to the nitty-gritty part of their discussions. What is their customer base like and do they have sales reps in different parts of the country? If the answer is positive you know they're committed to being a national player and you don't have to worry about getting stuck for days in CT or OK; if their core customers are located in MI and OH for example, and their marketing plan consists of using load boards and a couple of in-office telemarketers smiling and dialing trying to find freight, you have to decide whether or not you want to be in business with a regional or national carrier.
(Full disclosure - the above is just my observation as a spectator. I've never had any kind of relationship with Ex1)