(1) As per the present plans IR want to have 160kmph trains on identified 9 SHS routes and 6 GQ routes in long run, and desire to lengthen standard rake length to 26 ICF coaches (24LHB coaches). So the next version of WAP must be modified for optimal haulage of such trains.
(2) horse power of the new loco has to be higher than the minimum power required to haul standard rake length to 160kmph so as to have decent acceleration and consequently higher average speeds. This is very important because most of IR tracks shall have permanent speed restrictions and saturation of tracks and top speed shall be attained for lesser fraction of running time.
(3)...
more... One option could be to have loco at front as well as at end of trains so that total HP/acceleration/avg. speed of trains is high and the impact/jerk on the coupling is minimised.
(4) Train sets with multiple driver units is the best option in long run.