Arduino Uno + 2,8" TFT + sensors

Based on pinout diagram of the Arduino Uno and 2,8" TFT ( HX8347G shield) the pin RX, TX and A5 ar free to use, so i want to add some sensors ( GPS on TX RX and some girometer sensor on A5 ). Could some one confirm the usage of this port, and the load of the Uno for this kinde of applications ?