I would try a rayon wick especially if you are using higher wattages, it should last far longer if properly wicked. Also, maybe posting a pic of your build might help.. It sounds to me like your wick is not keeping up with your vaping style, and somewhat weirdly, one might think that having the tails very full and/or the tank full of cotton is the way to go. While it is true you need the right amount of cotton in your coil, making sure you thin and trim the wick correctly is really important. If the tails are too thick, the juice has trouble "penetrating" the tails, and it can actually lead to dry spots in the wick.
Could also watch some youtube reviews of your tank and see various ways of wicking it. Rayon solved every single one of my wicking problems though. I tend to want to overstuff the coil, but rayon shrinks when wet, so you do want it tight in the coil, while then immediately thinning and trimming the wick so it can wick effectively.
Best of luck. Usable (and inexpensive) rayon can be found at an Sally's location (graham cellucotton, just make sure you get the kind that is 100% rayon, can also be found on amazon and etc.)
Good luck,
Anna