so whats after gx1 and 25mm

i finally pulled the triger and bought the gx1 (body only) coz i have no interest in normal zooms , i am going primes

my first choice lens was the 25mm 1.4 coz of the focal lens

but i need something small to match the gx1

what do u recommend

12mm
14mm
20mm
45mm

i know its mainly about focal lens, just want to know ur opinions guys what is the lens u feel u need the most and would make a good match with the my only other lens 25mm

thanks