You are in the US. You don't have to buy Chinese ejuices which are only available as 100% PG or 100% VG. IMO neither is the most appealing. Nicotine in 100% PG can be harsh. Flavor and TH in 100% VG can be dull.
Most US juice makers offer PG/VG blends. I like a ratio around 70pg/30vg. Some like 80/20 for more TH. Some prefer 50/50. And some vape all VG or all PG.
PG lets through more of nicotine's harshness and TH, more flavor, makes less visible vapor
VG dulls nicotine's harshness and TH, dull flavors, makes more visible and persistent vapor
Also PG is very thin and can be more prone to leaking, VG is very thick and may not wick as well. A combination makes a better thickness.
Re your atty - could your cart stuffing be getting old and cranky? I don't know what your carts look like but maybe you could try cutting blue foam stuffing for a cart and see if it helps? There is precut blue foam stuffing for 510 carts at strictlyejuice.com or you can buy the uncut as Marineland Rite-Size U Foam Sleeve in the aquarium dept of Petsmart.
OR - apparently Hello 016 has a 510 adapter that lets you use 510-threaded attys and cartos. There are lots of attys and cartos available for 510 fat-battery systems. But I don't know what is the acceptable resistance range since some 510-threaded resistances are for other-voltage mods. I think (not sure) anything from around 2.0 ohms to 3.2 ohms would be usable? The lower ohms give hotter hits, the higher ohms give cooler hits.
If you want to try cartomizers with the 510 adapter, I use the Boge 510 soft-cap blanks from LiteCigUSA.net - I use standard because I have a plain slim 510 but you could try both the standard and LR ones. And I recommend a plastic or delrin drip tip to use instead of the soft mouth end cap if the carto is hot on your lips - LiteCigUSA.net sells them too. The drip tip is also easier to remove for adding juice to a carto. (don't drip through it into a carto - the juice would aim for the center air channel). the same place has a variety of 510 attys as well as 510 carts if you want to try a 510 atty.