I recently tried
juice from VaporRenu (the Swedish Fish is great!), and they offer an option to increase TH; I searched around for what they are using to increase TH without upping nic or PG:
VaporRenu
Apparently, they use a bit of alcohol to up the TH, but that could mess with flavor and/or vapor a bit. Might be something to consider...
(As a newb, I want to try out VV's and other set-ups to adjust flavor/TH/vapor before trying the Everclear route)
Just keep at it and don't go back to analogs!