1st you need to learn the differences between PG and VG.
VG feels very thick and heavy in the lungs, and it (personally) reduces my lung function & makes me wheeze.
PG on the other hand effects my upper respiratory section, my throat and esophagus. It stings them.
PG also gives harder Throat Hit, and VG softens the TH considerably. PG is more tart, VG more sweet.
This is why I prefer 25% VG and 75% PG for my perfect mix of TH,
If your Dekang RY4 is too flavorful, you should try mixing in some PG or VG. Just remember, it'll lower the nicotine. & higher nic content directly raises the Throat Hit. Less nicotine = less throat hit. If you mix 1/2 PG or VG you will reduce the nicotine & TH by HALF. This will also help to reduce the flavor & make your juice taste less offensive.
If you LIKE the flavor but your having a hard time with the TH.. Then you definitely need to reduce your nicotine level the next time you order. In the meantime, you can add a little denatured purified (bottled) water to your juice. I would add 5ml of juice to an EMPTY bottle and experiment with adding 2 to 3 droplets of purified water at a time. This will give you an idea of if it will help or not. If it does help, just do the math and add the drops needed to the larger bottle that you have. If you added 5 drops of bottled water to the 5ml of your DK-RY4, then add 5 drops of water for every 5ml in your larger bottle. This should reduce the throat hit, but it may also reduce the vapor output, because water doesn't create vapor like the PG and VG does.