Yea, generally in early poarts of the games, go around the hills, only use the lowest hill climb (unless very few wagons). The early steamers can basicly do any turn in full speed (or almost)
When 1902 arives a dubble in speed and a lot more puling power, its better to go mostly over the hills or a hybrid where goes party over and partly around.
Note that placing a up hill part like 500 meters out side a station is a dumb ideá. Sould really try to make it flat until 500 meters from the station, than down hill for 500 meters or so, this give the trains optimum acceleration