effects of hFE in emitter follower?
Advantages of higher hFE: 


Higher input impedance to the circuit
Lower output impedance


This way the emitter follower load effects to previous and next stages are reduced.

Disadvantages:


Depending on the polarization of the transistor, high hFE can affect negatively the stability due to variations on temperature.


References:
Emitter Follower, Ruye Wang, Electronic Circuits - I. pp. 1-21, A.P.Godse, U.A.Bakshi