You probably need to add more DMT to the mix. 1g per 4ml is adviced other places on the Nexus.
I am pretty satisfied with the vaporesso veco tank. Small ceramic coils with SS coil you can use with temperature control. I use the 0.3 ohm euc coil at 45w and 260C.
I still need 3 big hits to break through, but it will get you there.
You Can also check out the E-mesh thread in the welcome category, my favourite one hit breakthrough tool. I prefer to get it all in one hit.
Cheers