I think GNE needs something bigger for the X66 or increase the frequency the latter they're in no place to do, however every times I've been on it its been rammed, today it was an absolute nightmare, thankfully someone at GNE realised and upgraded them to Deckers (TVT, E400 & G2 06 Plate I think). 

Also GNE must be making bank off the X66 its a £3.80 return (which is quite expensive for a 10 min journey)