I have vaped all kinds of e-liquids including those based purely on Propylene glycol, Vegetable glycerin or the combination of two (70% VG / 30% PG & 30% VG / 70% PG) and found e-liquids with higher concentration of VG to be sweeter in taste, better vape producers and probably safer for health since VG is 100% edible as it is used in food products as well. While PG is used in medicines for example ear drops contain propylene glycol.
Generally, most vape juices are based on the combination of two VG and PG and usually percentage goes be 70/30. Try to avoid e-juices that got higher concentration of PG. Manufacturers put propylene glycol more to cut the manufacturing cost and to keep the prices low since vegetable glycerin is expensive than propylene glycol.
If you want to make your own e-liquid, you may use the combination of both VG and PG or use pure vegetable glycerin and dilute that with PG based flavors or water (10% water in 100% VG should be enough). 100% VG based homemade e-juice recipes are also available. So check them out. My personal choice would also be 100% vegetable glycerin based e-juices. If your vaping device has got liquid spitting issue, then VG based e-liquid is safer for you. Swallowing liquid based on higher concentration of PG and nicotine can cause nausea, headache and other health related issues. So better get your MOD fixed or switch to pure VG based liquid with no nicotine (if you were not a chain smoker already, nicotine free liquids still could pacify your urge of smoking)
100% VG based e-juices could increase the maintenance requirement of your vape atomizer since it could get stuck to the coil. But that shouldn’t be the matter of concern when you consider your own health important. Atomizer tank and coil could be cleaned easily. You may change the coils if burnt since these are not too expensive. You could also re-build your coil at home using 26 gauge Kanthal wire. Kanthal is the alloy of iron-chromium-aluminum. I would recommend to use Kanthal since it is safer compared to coils made purely of nickle, chromium or aluminum.