There are a few differences between 104.3 and 105.1 that could work SLIGHTLY (though admittedly not much) in 105.1's favor. The signal for 104.3 isn't quite as good as the one for 105.1 in Louisville. I could very rarely pick up 104.3 at home, and I even live in an area of Louisville that is supposed to have their strongest signal. On the other hand, for 105.1, I rarely have trouble picking them up. Also, 104.3, as hard as they tried with the resources they did have, I still don't feel like they had enough resources to make it known that they existed. I would have never known 104.3 existed if not for the internet. 104.3 was run by a group that tried very hard, but really has to make that difficult decision to either be a really good station (they were) or to get the word out there that the station exists to those who didn't know it was there (they sort of did, but there wasn't a lot of it).
Maybe the real answer is 93.9. If Alpha could pry 93.9 out of the "cold dead hands" of Cumulus, and of course, somehow get rid of 105.1 (I'd even settle for somebody like "Educational" Media Foundation taking 105.1 at this point, if it were to keep 93.9 out of the hands of some "non-profit" radio owner), then maybe they could have a fifth station that works.