Jacob, I believe it was expressed that you did not provide enough information for anyone to help you with the situation. What Device and RDA are you using? If your DIY has too much flavor, the flavors will taste burnt and some can gunk up your coils faster. If your juice is 100% VG it is too thick and won't wick so you are vaping a burnt coil. You could also have your wattage too high and need to turn it down, or like stated your nicotine may be too high and you need to bring it down to under 6mg.
Are you using a Tank with the RBA section, or a RDA (dripper)
Before you spend money on a new set up, I would want to figure out where the problem is so it doesn't happen on the new set-up as well. if you changed the coil and still have this problem, a new mod may not solve the issue.
So I went back through the older post and it looks like your coil resistance and wattage settings are fine. How about changing your wicking material. I have noticed that all organic cottons do not vape the same and I have had some that seem pretty harsh or just don't taste good. Try some cotton bacon that works best for me on flavor and smooth vape