I am the same way. It is very subjective, even to the gear used; wick, coil, wattage, etc. I started a spreadsheet from the beginning, and yes I may be a little OCD, but I have found about 15 flavors that I like. As I order a flavor that I like, I order one from the same vendor that I have not tried. Slowly, but surely I have found about 15. I am still going, it is just part of the gift of switching from cigs to vaping.
Right this moment I am vaping Smurf Cake, go figure.
As to out and about emergencies, I just keep juice buried in the car and change it out. Being at such a low nic level now, I really don't get emergencies.