I turned on the attenuation on the new OKC system and it seems to improve satisfactory the reception as I drive around. It may be cutting out some transmissions, but what I don’t know doesn’t hurt me!You're an ideal candidate for the Comet CH32 Miracle Baby antenna!
Amazon.com: Comet Original CH32 CH-32 144/440/900 MHz Tri-Band Miracle Baby Handheld Antenna - BNC Connector: Electronics
More than enough for the close tower, and the smaller size may help minimize interference from the more distant towers. This is a case where less is better. I'm in the midst of a 9 tower system and it works great for me!