Here's a better defence.
First, build 2 Light Towers (Range) at an enemy.
Next, start building a Cannon Tower in front of your Light Towers (If it can be hit there then shift it a little)
Follow up by constructing a Light Tower and an Elemental Tower.
Build a Cannon Tower nearby.
Repeat until your opponent has few or no towers left.
Once you throw your opponent out, take over his spot and start teching.
This will work as a defence or an offence. And much better than just mass range. Mass Range will work but you'll need stuff like Cannon Towers or some weird damage tower to cover for you.
*When I say build a tower, I mean build the strongest tower possible (EG. Light Tower -> Elemental Tower -> Mage Tower) If you can build Mage, if not, Elemental or Light.