Repeater Bolt Throwers are real machines of war. Since the crew is very vulnerable I put them at the back on a hill with your unit or units of archers. I use volleys on units and single shots on characters with high toughness. Decide for the Bolt Thrower to take out deep ranked units and heavily armored ones while your archers pick on weaker targets.

Tiranoc Chariots have the power to just run over their enemy. I find that these work best in groups of two or more depending on how many points you are using. Because if you  just have one it will easily be destroyed so with more they will be able to back each other up. I like to have one of the crew with a spear and the other with a longbow. This way you can start to cause damage before you charge. I like to heavily arm the crew for more protection and also to give wheels syths.