I have a smok pen 22, I have been using smoozie Maui Waui e liquid. I have to either wait a while for the juice to soak every few long hits or I have to drop some juice down the top. I tried loosening the cap different amounts it doesn't seem to help, some people said it would. I'm not sure if I need to use different E-liquid like a clear one or what, but I hate having to wait in between hits especially if I already filled the vape with juice. I tried priming the coil when I first got it there was no good there.
I don't have that ecig, but FWIW I have a few thoughts on your issue anyway
It seems to be an unregulated power supply, meaning it will give you power as per the resistance of the coils which for the 0.3 ohm heads I see online would be around 35 - 45 watts depending on the state of charge of the battery. So with a fully charged battery you'll be getting around 45 watts. Less power will help eliminate burning, but you're stuck with this ecig. Higher resistance heads will reduce the power, but I don't know if they are available.
I have no idea how good the heads are, or how consistent their quality control is. Some manufacturers are poor on this. Your juice is 70% VG so it's on the thicker side which will slow down the wicking. On the other hand 70% is pretty common and there are higher VG juices on the market which are thicker, as well as lower VG juices. Adding a couple % of water to your juice will thin it out, it's easy to try with a small amount of juice and will not affect the flavor noticeably. I would use a small graduated, very clean, syringe to try this. If you end up liking this solution, I suggest you use distilled water for safety going forward.
The cotton could be packed a little too tight in all their heads, or just on the one you have if their packing is not consistent. You can prod gently into the wicking holes with something like a pointy dental pick and and open the cotton up a bit. If you try this you need to be careful not to move the coil wires inside the casing so they end up causing a short, so gently and carefully is the way to go here. If you open the cotton too much you'll have leaking through the air flow opening.
You may know all this already, but just in case here's a good general
article on the topic.
Best of luck with it.