A lot of people here will denigrate the idea, but since you are in RDU, you should look at Southwest.

Get 100 credits in a year (you can greatly augment the total with credit cards, hotels, and rental cars) and you can take a companion free for a year, even when you are traveling on a reward ticket.

Best deal out there, IMO. Come over to the Southwest fourm here on Flyertalk and take a look.

If you are going in at an entry level, and get assigned to a longterm project, you may be put up in shared apartments and given leased cars to share, which cuts down on the miles you can accumulate. The firm I used to work for did this.

Some firms will pay for your weekend turnaround to other destinations than your home office as long as the ticket costs less. I ran into some people from my firm in Mexico City once, down on a long weekend with the flight on the company. If you find good prices, it might be possible to pick up a few extra miles that way. And if you are sent to a nice area and are going to be there for a while, stay over the weekend. Usually they'll pick up the accommodation, and you'll get a weekend to explore. It will make up for the weekends when you are there because you need to put in another 12 hour day.

You probably won't start out at a client's the first day, so have a chat with someone at the office. They will, I'm sure, know what the best deals are. Everyone I knew could tell you exactly when they were going to attain status, as in "When I get off the plane seven weeks from now, I'll have x status."

Concentrate on one airline. For some reason, I think USAir has a hub in Raleigh.