I know some other people who work with the RDAs on a regular basis but tend to stick with either the fruit punch or tobacco flavors for the most part. Some of them go much further into sub ohming while most are staying above the 1ohm mark as a rule keeping things a little more down to earth there.
Here by mostly using one brand and model tank I am able to make some rather interesting observations when either turning up or down the volts or watts, or simply moving the same tank from battery to mod all set at 7w to see the results. Some seem to vape better on one of the Vamos(V5 and now V6 previously V2), MVP2.0, VTR all running 18650s with the VTR now running a flat top high drain when finally located! No one had flat top anything which the VTR takes.
I have my own primary flavors out of several by multiple vendors like a tobacco/menthol(Pioneer - CCV), a strawberry/watermelon(Melon Twist - CCV), another menthol/tobacco(Madvapes and EcigCharleston both) which is light on the menthol, Carmel Cappucino(Caramel Cap-CCV), a mocha/coffee type blend(Mocha Java-CCV), Chocolate/Tobacco for a switch!
(Vertigo - CCV) and several others since I sample everything from that vendor(CCV = Crystal Canyon Vapes
). Others like Strawberry Cheesecake(Mom&Pop Vape Shop) and Peanut Butter(Nettmix) and one you can no longer get while they still have the Fudge brownie was the Chocolate Peanut Butter Brownie they did away with without any notice of disconinuation only seeing the "notify me" on the page.(sweet-vapes)
Now when you mentioned having two batteries or other set up to have more then one flavor ready try about two dozen here! Each and every battery including some non variables has a different flavor or a mix up except a few with the primary menthol(Pioneer) I keep going in case of an allergy attack! But one word of caution when having more then one sitting around in a tank too long is running into a kind of flavorless or bad throat hit(hot in back of throat) problem!
Here with too many flavors collected over time but not used up fast plus new ones coming out or found I am now vaping off what is in the tanks and setting each one aside until I catch up! I have spells where either I dust off a tank in about a day's time or only get about 1/8th vaped when having 3 or 4 going at the same time.