Nice build like mentioned iv had more success using 30g when venturing above 1.2ish ohms.
Heck i used to run a 3ohm coil with 30g on a igoW at 15w on my vamoV5 and it was enjoyable.
Id try hitting 1.3-1.5 with that 28g around 1/16 bit
If ya get 30g you could go higher in ohms and still get great results around 1/16 drill bit.