If the antenna is in the attic, it's low gain, building penetration loss and the terrain are all combining to leave you with little hope for reliable reception.
The single most effective improvement would be high mast or tower mounting, outside in the clear. It would be interesting to see a TV Fool report for 40' and another for 60'.
The signal conditions shown in your current report call for an outdoor mounted antenna that has substantially more gain. I would consider a Winegard HD7696P or HD7698P at a minimum. There are other 'premium' solutions that can be suggested if you'd be willing to consider a multiple antenna / multiple HD HomeRun installation.
http://forum.tvfool.com/showthread.php?t=820