Hero engineers.

Well... I often play as the Iron Lady (Daleb)... Has anyone tried developing the entire series with the Rangers? They don't have a hero-engineer, but you can get up to 4 skills for the ballista: ballista, rapid-fire, enchanted, and fire arrows... I just haven't had the chance to try it... does it even make sense? I mean, if you develop Chaos magic and put Shock Earth on the ballista (and of course, you'll have to develop mana too)...
P.S. I also really like Kaspar with the plague tent... I almost always take him as an additional hero at the beginning...