Magic did the light rock/good time oldies for several years in the early 90's. I got to Fayetteville in January 1994, and, shortly after that, it started doing all 70's weekends. Z-98.3 almost immediately launched "Disco Escape Weekends," which was the greatest hits of the 80's all weekend long.
I suspect a lot of the problem with classic hits in NWA is that there really aren't that many signals that cover the entire market. When the frequency allocation table was established, there was really no way of knowing that area was going to explode in population. Even when I was there, the place was booming, but I don't think anyone thought it would be what it is today. More signals cover the entire market, or at least the bulk of it, than did 25 years ago, but that area still has a lot of signals that cover either Fayetteville/Springdale or Bentonville/Rogers but not reliably both areas. Terrain there, especially around Fayetteville, makes a lot of the area signals do worse than they do on paper.
While the area has a lot of 18-34 audience due to the college and a more ethnically diverse audience due to the poultry processing industry, I don't think it has any shortage of potential classic hits ears. In addition to all of the people moving there to do business with Walmart, a lot of my friends from college are still there. I don't know how representative of a percentage of the students at the time that is, but that area had a lot more jobs for us than it did a few years earlier. Those jobs have only grown since. All of them are square in the crosshairs of the classic hits demo. So, the problem wouldn't seem to me to be one of demographics.
That's also a signal that doesn't cover the market very well. It's a C2 that's well outside of town. When I lived there, it was KDAB, which aired a southern gospel format as "Higher Power 94.9." It seemed to really splatter over 94.7 and 95.1 at my apartment, but, as soon as it signed off (which it did at 10:00), KTTS-FM 94.7 and KMXL 95.1 would come booming in. It's really good in Fayetteville, Farmington, and Prairie Grove, but it's pretty mediocre elsewhere. You can get it on a good car radio or home stereo in much of the area, but that's about all that will get it reliably, especially in Rogers and Bentonville. I liked the old "Kruz FM" format 94.9 did about 10 years ago. I'm not really surprised it didn't do very well, though.
Websites are usually low priorities for most operators. I noticed that, too, but I didn't find it that surprising. Hog Radio still has its website as well.
I have no idea, though I wouldn't be surprised if it turns out to be nobody. Cumulus tried oldies once before with Cool 94 and didn't like the results it got. Granted, that was a long time ago, but you usually don't go back to doing something that didn't work before. Plus, classic hits/oldies hasn't worked that well for anybody. Then again, Cumulus has gone back to AC on 94.9 multiple times.