Looks interesting, you expect this to give the lowest power consumption? Indeed with ESP8266 it will probably be hard to reach very low power levels and run for months on 1 battery?. It seems the ESP32 will have some better low power features?
Besides low power consumption a low price is also interesting of course 
, in that regard an ESP8266 together with a SX127X board would probably beat most other combinations? (as you need a more powerful uP to implement the LoraWAN stack and need some GPIO ports for attaching sensors.
I'm still wondering how to use all these GPIO's on the RN2483 in a usefull way. AFAIK you won't be able to do anything like SPI, I2C, 1-Wire etc. So I guess it is mostly limited to reading on/off values and flashing LED's or driving a single on/off output and you will need to have the more powerfull "protocol" ports of your uP to do things like that?