There are several ways to approach your situation. If you are interested in receiving every possible signal, you are in a location that lends itself to the DXing hobbyist.
Your OP sounds like you want simple and reliable though, so...
Any of the reputable antenna brands 4-bay UHF panel antenna would be a good choice.
U4000, DB-4, DB-4e, CS4, CM-4221 or HD4400.
http://www.antennacraft.net/Antennas/AntennasUHF.html
http://www.antennasdirect.com/store/...-Antennas.html
http://www.channelmaster.com/Channel...ntenna_s/3.htm
http://www.winegarddirect.com/cview....nly%20Antennas
With the antenna mounted outside, facing between 190° and 220° you should have the major networks and enough signal power to drive a 3-way splitter with no amplifier.
I think this simple option may leave you with no CW, ION or MyN.
If you want to consider other options, let us know what you need/want.