Do you mean changing the polyfil inside and use something else or just add diff e liq in them. I am thinking of mixing my own e liq does vg or pg give better throat hit?
PG and VG dont give any throat hit, but determines the type of vapour you get:
PG seems to make a misty type fog, VG makes a thicker, dense vapour cloud. A 50/50 mix is pretty good, or somewhere in between.
Throat hit (TH) is usually created from nic level and/or alcohol and/or certain flavours...namely menthol.
If you find your comfortable nic level isn't giving enough TH, cut your juice with some high alcohol % vodka, or try mixing in some menthol juice.
I just kept upping the nic until it was satisfactory, and found 36mg to be good .. I think it may be a bit high though and am going back down to 24mg.