It's possible that even though your FM (channel 6) omni seems to be doing great you're probably only seeing the tip of the iceberg. Get the biggest antenna that you can stand asthetically. You can never have too much antenna and you can never have too many stations.
I took the liberty of doing a TV Fool of Pell Lake. I put the antenna up 500 feet to get the lay of the land. It looks like maybe you have Madison to the northwest and something to the southwest (not that familiar with WI geography):
It's only marginally more difficult to install a big antenna than it is to install an average one. And once it's done you won't be wondering every time some marginal DX starts to break up and drop out. You'll know you made a good effort.
Here's an AK thread about members' antennas (TV, FM, AM) but unfortunately you might have to log in to see the attachments:
Antenna Pix: DIY and Store Bought
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