I am going to opine that lung capacity (and perhaps build) are the biggest factors and yes you need good airflow to get to a really cloudy build. I think the pros use JUST VG, honestly.
My kiddo came over last week and began ATTACKING them, he toasted MANY of my tanks before I noticed he was inhaling for like 300 seconds. He kept complaining about my DIY juices, LOL, until I noted he was TORCHING my wicks.
This week he tried the Pharaoh RDA I had. It was only a 0.75 build (with a ton of airflow) on a mech, and honestly not crazy POWERFUL batteries and my juice was only like 55VG.
That kid has a future in cloudchasing but I don't mention it EVER because so many (well some) of those comps can result in BLOW UPS if you don't know what you are doing.
I bet you ANYTHING though, with the right build and battey and juice he could win something. LOL. He only smoked extremely intermittently before becoming a vaper, and he seems to have GREAT LUNGS. LOL.
If you are a long term smoker well that task may be harder.
It's true though not so much talk about cloud chasing on ECF. I'm gonna bet the MAY be better forums for you, etc.
I still say it's about 90% lung capacity because all the real cloud chasers do it the same. Build a truckful of wire I their build, use VG only, probably hit the fire button WAY before inhalation starts, so it tends to come down to lung capacity.
Just... BE AWARE of safety issues.
Anna