I'm one of the lucky people who has really tolerant taste buds so I can vape just about anything. I'm also egotistical enough to actually believe that the worst DIY joose I've ever made is better than the best pre-made joose I've ever tried. That said, Mt Baker's Cinnamon Roll juice is pretty good and most people like it. All you can do is experiment until you find what hits the spot. For me, it tends to be fruit and mint (or menthol) flavors. There are definitely some premade jooses that have almost cult-like followings, like Pluid, which I've never tried and feel no need to try.
Depends. Not sure if I've ever tried vodka with Dr Pepper but I probably have, since I've tried and liked vodka with everything I could think of. Vodka and Coke, in my opinion, is just as good as the better known combination of Rum and Coke. Tonic water and any liquor is also good, in my opinion.
To
@Iffy's amusement, I find vinegar, water and any liquor to be a good combination. On a total tangent, I've recently been trying out a bunch of different ales, and wow, adding liquor sure does kill the wonderful head that ales tend to have! Nevertheless, I find the taste of Everclear and good ale, or tequila and good ale, to be excellent, even when the head is dead.

Mixing ratio: 5 to 10 parts ale to 1 part liquor.
Please, don't expose those of us who pretend like we understand Ohm's Law. (That would be any of us who profess any understanding of Ohm's Law, because nobody actually groks it fully.) Ya know what? You don't need a chart. You just need to experiment with different wattage settings on the iStick 30W until you find what tickles your fancy. For myself, I never found anything over 15 watts to be good, preferring the range of 8 to 15 watts. Other people, though, will swear by higher wattages. It boils down to what tastes good to YOU, not what tastes good to somebody else.
If your delivery device (tank) has the ability to adjust airflow, that is another thing that has a large effect on both flavor and vapor volume. You have to experiment with that as well.
The worst hit I ever took from a vaping device was better than the best drag I ever took from any of the 800,000+ cigarettes I smoked prior to vaping.