Seems like you're using 4 mm, it looks too big for 3 mm and the math doesn't work out right:
Coil wrapping | Steam Engine | free vaping calculators (link includes settings already).
Power you're using is high for them unless you are taking short drags and not letting it reach full heat, or there is loss. Check you mod specs for voltage limits (taken with a grain of salt).
The common idea of higher resistance inherently being lower power and using a smaller, lower power coil is based on the history of mech users, the experienced of which would know to use thinner wire in that case. With regulated, this is not generally required and this cause much confusion
(here). If you use
the same wire, a higher ohm coil will be larger (e.g. more wraps or larger ID), handling more power, and vice versa. Of course, a smaller coil would be a great opportunity for smaller wire than that too. The larger wire tends to conflict between overheating and slowness more anyway.
Safety at a certain power level depends on your batteries handling it, and also the ejuice not overheating to dangerous levels (I dislike overuse of the term "cotton burning" because this is only one form of overheating). The coils being large enough for the job is essential, as is Airflow. It is best to see it as a whole bunch of seperate limits, the lowest of which will dominate, and proportion is reached when all match.
I think, when choosing a vape, the first consideration is technique and preference, followed by choice of atty, drip tip (HUGE influence) and airflow setting. That combination will tend to want a specific power setting (not factoring losses) with any coil close enough to even permit trying it. Then home in on the exact coil.