Don't know if this helps, but if you love nicotine as much as I do it might.
I had the same problem as you. Wheezing and lungs felt heavy. But I was using a lot of sub ohm stuff. So I put the big stuff down for about a year.
After I stopped sub ohm vaping, I started using the blu kit with the pvc. It was good and gave me a good dose of nicotine when I needed it. The only problem was that the charging kit kept breaking and the carts were pretty expensive. I think they were about 18 bucks for three and only lasted about a day and a half. Two days if I was lucky. So I gave up on those and now use a Mark 10. A little less expensive and they work great. I don't get near as much vapor as I used to, but I get more than enough nicotine.
It didn't take more than a week for my lungs to start clearing up. Today I went out and got a new Smok Big Baby Beast, so I'm starting back on the big stuff again. If my lungs start feeling weird again, I'll just go back to the Mark 10 again. There really a pretty good vape.