I know that 2A is recommended; however I do not plan on making phone calls, just text and e-mail.
It's not just for phone calls, it's for everything.
Are you sure the device is registered to the network? There is an LED that has a varying blink rate to indicate network registration. I've seen people get confused by the frequency of the blink rate so the easiest way to tell if the device is registered to the network is to simply call the number from another phone. Depending on the service provider it should go straight to voice mail if it's not registered. If it is registered then it should ring continuously.