In discussing this very thing with a number of cell phone salespeople, and heaven knows there are a lot of them, the concensus was that there is very little actual reception difference between the expensive phones and the cheap phones. Rather than looking at the made-up "list" price and whether it has a camera or camcorder, the biggest issue is the quality of the sound from the unit. If the sound is clear, you can understand even a weak signal better. A surprising number of expensive phones have lousy sound quality.
Other suggestions for reception... Get a metal replacement antenna for your graphite one, if yours screws off. Get that silly stick-on thing that looks like a big, gold-tone printed circuit - most say that it actually helps some.
Thoughts... Get an extra battery right away. Keep a 12-volt cell charger in each car. Get an emergency power pack that uses AA batteries. Get an extra charger for travelling, in case you lose it.
Most of these things are available for only a couple of bucks on the web or through eBay. Buy them all at once to save on shipping.
Best wishes,