Increasing vapor and flavor can be done several ways. Flavor I found is boosted by using more PG in your mix of liquid, though if you like more visible vapor, you want more VG at the cost of flavor. As for as I know, even with less visible vapor, you get more flavor and the same nicotine (on higher PG). As for more vapor, you have several choices. Current flow needs to increase which adds more heat. Here are your choices.
*Lower ohm
coils
*More voltage
*Mechanical
mod
Some people will disagree with the last one, but I have tested that on mt ego winder at 3.7V and my mechanical
mod (K100) with a 3.7V battery (metered at 3.7V, not full charge which is higher), it gives me more vapor. As for the other 2, they BASICALLY have the same effect. In the end, it's about adding more flow to the other end, and they both seem to be similar. For me, voltage seems to heat it up faster than low ohm, but both have a place. Remember, with higher wattage (low ohm OR higher voltage) you need more air flow in most cases as you can't draw fast enough to not burn the coil. The air flowing past will cool it some, so it's also a fine line. If you can afford one, try out a rebuildable atomizer and build a low ohm coil (but don't go sub 1ohm at first, they can be dangerous, same as high voltage)