From my experiences with both helicopters, The ghosthawk definetely seems to have higher armor value and is more difficult to shoot out or disable, As well as being significantly easier to successfully belly drop with, Even if it was considered to be added for rebels, The price tag would have to be considerably high.
Huron's on the other hand I think would be a better alternative to be added as another rebel helicopter, Relatively easy to disable, More than enough room for passengers, While also being decently fast.