Please help with Eris issues...

[killerloon]

I recently talked my mother into buying an Eris after I finally bought a Moto Droid a few months back. She lives out in the country and dosnt have the best signal with the eris (1-2 bars at the most where as with my droid I get 2-3 bars out there). The battery only keeps a charge for maybe 3 hours when shes home. It finally dawned on me that it was because of her reception issue that shes having a short battery span. I checked her battery usage and sure enough her cell standby was using 73% of her batt. My wifes eris sits at about 54% in town and my droid seems to hover around 6%. Keep in mind these are all stock android phones. Im trying to figure out what (if anything) can be done to improve her Batt performance. I dont want to root her phone. Shes been running adv task killer since day one and we are getting nowhere. If anyone has any idea one what can be done please help me out.