I use to take zinc when I first started getting vapors tongue. Cured it pretty fast for some reason. I think it had something to do with the mineral deficiency from years of all the crap loaded in cigs to force you into withdraws. I don't really get the flavor loss now.
Now, I do get tired of some flavors that I tend to overvape. Meaning, finding a flavor I like a lot, & vaping it till I wear it out like a good song that gets played to much on the radio. There are A LOT of juice's I use to love that are either boring now, or I just can't vape any more. I'm guessing that may be more of the issue with you....?
All I can suggest is what work's for me. I've gotten to where I can't vape carto's, clearo's or anything like that anymore. I've gotten spoiled from rba's & especially rda's. The flavor & vape, to me, is way better. Not to mention easily allows you to really drop the nic & stay satisfied. I know I've read several of your post, just can't remember what type of equipment you prefer, or are using.
Maybe you just need some juices to knock your socks off. I've been thrown into, in your face, bold juice's. Anything from Mad Murock, Next levels purple people eater & agent orange, space jam's robo fuels, Jameson's Irish vape juice's. Check out Elevated vaping. They have a lot of really good, bold, juices. I'm sure other vendors sell those same juice's, maybe for cheaper, but at least it's a starting point with some higher caliber juices.
Maybe you just need to acquire some new toys to vape on. When I get bored I find a new device keeps my interest.
Lol. I guess what I'm saying is...buy some new rebuildable's, get some really good juice's, & get some new mods. Should work good enough for another year. Then we'll get back together next year & make a new newer plan.
God I love vaping!!