Y'know, I pretty much went through all this when I picked up my new bike. I have an 80s steel roadie, made in Japan, entry-level, lots of crappy bad tech (like Biopace chainrings and Shimano Light Action derailleurs). It was comfortable enough for a Century, but ultimately, upgrading it simply didn't make sense.
You're better off using the Bridgestone as your beater / backup bike, and getting something else for long distances. With a new bike, you'll get at least a year of tune-ups from your LBS and hopefully a real fit as well. For all you know, the Bridgestone could be the wrong size....
The thing is, many different types of bikes are suitable for LD. Performance road, Roubaix, audax, cross, even touring will all work. The 1st two types will be the hardest to get wide tires & fenders, the others are no problem. I'd try to figure out what else you want to do with a bike, select a style, do as many test rides as your LBS can stand, and see how it goes.
By the way, LHT's are pretty much back-ordered right now; Surly can't make enough of 'em. Another good thing about the Cross-Check, I had mine in less than a week.
