If you want big clouds, you'll go through more juice at each puff. That's just plain logic. If that's what you want, make a longer wick that holds more juice.
The trick with long wicks is to reconcile good immediate feeding of the coil (i.e. you want some of what you drip into the atty to land directly on the coil, and the rest on the tails of the wick for "storage", so you don't have to wait for the juice to creep its way down the length of the wick to vape), leaving enough of the coil exposed to the airflow without flooding, leaving a direct escape path for the vapor from the coil to the drip tip, and maximizing wick length.
Depending on you particular atty, it can take a lot of experimenting to find the right setup. But here's a trick that helps: leave the tails of the coil attached and use them to support the wick and lock it in place.
Alternatively, you could try chasing flavor instead of big clouds
For that, the quality of your wicking job is essential too. In fact, I find a good wick is a lot more important than a good coil...