I almost always use 2-time for two heroic dice. I find that I often end up spending more time on boxes that I couldn’t cover anyway, when I didn’t use the ability. Use kite to your advantage when you can. Only use the 4-time ability for extra difficult challenges.
Do you play with or without the extra campaign abilities? I like to play with the added Basic Ability card and use the Precision ability for my Archer.
I always play in campaign mode. I use Precision and the Dungeon skill tree.