I have a good idea why dont they rename the northern provinces of Afghanistan - Tajikistan, Uzbekistan, Turkmenistan - it surely would reflect the ethnic make up of the area.
the word Pakistan is abbrevation of P: punjab A: afghania K: kashmir S: sindh Tan: balochistan
N.W.F.P is always refered as afghania not pakhtunkwa in history, Afghans in settled ares of N.W.F.P have actually came from present day afghanistan because they were pushed here by stronger tribes there. The original people of N.W.F.P were hinkis who r related to punjabis. Because afghans were fierce warriors therefore they easily defeated these people and colonized this area. many hinkis were pushed beyond indus river, others remain here, some completely assimilating into pashtuns while other retain their identitiy successfully like in kohat ,peshawar or other areas. thats why people of N.W.F.P are darker as compared to afghani pashtuns bcos they are not pure as it is assumed. unlike eastren d.i.khan hazara is closely related to pashtuns but it is strange that unlike seraikis they r very anti-pakhtuns. even hinko speaking pathan tribes of swatis, tanolis,jadoons, tarins etc r against renaming of province.