RFID is quite difficult to get working. Which type of RFID are you going to use?
If it is the simplest 125 kHz RFID, where the receive and transmit are on the same frequency, the limitation is generally on whether you can see the return signal from the RFID tag in the huge signal that you need to drive the coil.
Systems where the return signal is at a different frequency can get a better range.
Generally if you want a large range, you need a large reader coil and a large amount of power. If you have a small coil, the range will be small.
If you have to send data to the tag, it is usually necessary to make sure that the magnetic field from the coil turns on and off quite quickly, which limits the Q of the coils circuit that you can use. That in turn means that quite a lot of power is expended just keeping the magnetic field running. However, it might be possible to open the tuned circuit to stop the magnetic field quickly, keeping the energy in the capacitor, and allowing the field to be restarted quickly, even with a high Q coil.