I have several PVs. Now during the day I pretty much use my eVic when I am at the office or my eGos when I am on the move. I switch up my juices every hour or two by loading up 3 or 4 EVODs each morning. When I get home, I have my lavatubes and Vamo set up with a couple juices, my eVic set up for my EVODs, and maybe another option with my eGo twists. I change juices all the time. Every once and a while, the same juice will taste really great, and I will vape it all day. I also make sure I have some MOV, some HHV, some Highbrow, etc. By switching vendors as well as flavors I feel I improve my chances of avoiding "flavor fatigue".
Maybe this will help you. Sorry to hear you are struggling with flavors. If you have limited hardware for all this switching, just get a few clearos and load them up for switching out. I try to do my switch-a-roos with eGo threaded devices rather than 510s, since 510 ports always wear faster in my experience. Good luck!