Makes trains feel more 'bulky' - Increases locomotive weight & power, decreases top speed, increases cargo wagon weight & capacity.
Increased cargo capacity is solely to offset trains being slower; cargo wagons should still achieve similar throughput to vanilla trains. Fluid wagons are untouched.
UPDATES
14/6/2017 - v1.0.1
*Rebalanced friction & power:weight values; unladen locomotives and short trains accelerate much slower, long trains (4+ wagons per locomotive) should be relatively unaffected.