Towers are good if ur in a war and need to leave for some reason for a extended amount of time other than that use pots
I have never used a tower cause i hear they suck. They don't increase max plunder at all, and give no extra troops... Just a little bit of defense stat.
Pots are crucial, towers or not. Whether you want towers too depends on your situation. Give us more details. Most players only have pots and no towers. Others have many of both.
There is an argument for spy towers if you're an attack build, but I think def towers are a waste. They don't make plunder & are useless if you know how to battle from the pin position