You could try Airvoice+Moto G.
Airvoice has monthly plans as cheap as $10 a month, and I believe the remaining account balance rolls over as long as you continue to renew. How many is "a lot" of texts? If you send them to only few places, might it be replaced with a messaging app like Kik? That would actually be cheaper. Nevertheless, if you feel you need texting and 200 is too constrained (150min talk=$6, leaving $4 for $0.02/text=200), they also have a $30 that is unlimited talk/text+500mb of data.
All of this is on AT&T's network, but currently without LTE. That won't be an issue, though, if you go with the Moto G, as it doesn't have an LTE antenna.
2xMoto G = $358+shipping/taxes
Another option is to look into purchasing a Nokia Symbian handset or a used phone, although the Moto G is fairly competitively priced if you are looking for a smartphone.