If you're looking for more throat hit, higher PG & Nicotine %. If you're looking for bigger clouds, a higher VG %. In most cases, for a balance between the two, a 50/50 PG/VG juice is suggested.
In most all cases, I use 1.5-1.8 ohm coils, a 60/40 or 70/30 juice and my wattage is set to 10w. Vapor on the Protank 2 is great, but you're not going to get huge clouds like you see on RBA/RDA's due to airflow restrictions on the Protank/EVOD/TS3's.
That said, unless you're already in to building your own coils, an RBA/RDA isn't recommended as you need to know what your device is able to run, an ohm meter to check resistance etc.