Hi,
The datasheet of nRF24E1 is not very clear regarding the required load for maximum transfer, but if you look in the datasheet of nRF2401A, you will see "The load impedance seen between the ANT1/ANT2 outputs should be in the range of 200-700ohm. A load of 100ohm+j175ohm is recommended for maximum output power (0dBm).". Since the RF cores are identical, the same should apply to nRF24E1.
I've used the matching network from the picture, but with 3,3nH inductor ( I was unable to find 3,6nH in small qty), C11=C12=1,5p and without C13. With these values, the output was around 0dBm, measured with an R3131 SA. The measurements were performed without modulation (bursts of carrier only). The components are all in 0603, the only exception is the 3,3nH, which is 0402.
/pisoiu