Moose are hilariously under powered in this game when compared to horses in the real world. in fact 3x more powerful than horses. a Moose realistically would have far less difficulty with steeper grades than a horse would harnessed to a cart. increasing moose strength to the grade point a normal char would have to climb would be far easier and more realistic. Moose can also swim .9 km/hr
other related considerations may be the inclusion of Oxen as heavy draft animals. or perhaps the ability to harness 2 animals. additionally the Trainer ability to train a draft horse also with higher pulling power when harnessed to a cart.