Without changing wire gauge, the only way to increase resistance is to increase the effective length of the wire - i.e. more wraps. Try going up one turn on it. If that's still too low for your tastes, go up another. Of course, inside the Evod base there's only so much room...
Yes, wrapping a smaller diameter coil (same number of turns) would mean less length, lower resistance.
What are you wrapping on? You want to be consistent in your builds. Change too many things at the same time, and you really don't know what caused the change