I didn't read all the comments so I may repeat what someone else has said.
The only way to safely ''water'' down the nico level is by adding a lesser strength nic of the same flavor, best bet would be to buy a bottle of zero, if you half and half some equals parts zero and 8mg you'll have 4mg.
I personally only make a large order of things I've tasted so I know what I'm getting, then I'll buy a box of carts and a bottle same flavor juice and refill, this saves money over buying blank carts. Blanks about $9, filled about $10, so yeah
If you like tobacco flavors your best bet is to stick with what you know. Hilton, Dunhall etc. When you are ready to venture out, the fruit and dessert and all the other flavors will be like vaping for the first time!! But you have to be ready for it. I wasn't for a few months, and certain flavors that I hated have now become my favorites. I went from tobacco to coffees, then all the others, but everyone is different. I like to refill cool carts with wow juices. I think V4L has chocolate down to a science, so anything with chocolate is bound to be really good. Taste is subjective and you have to find your own groove. I also love the caramel apple, butterscotch and in fact can only think of one flavor I don't like, and I'll probably like it in a few months - lol. Vaping is a strange and personal trip, but if you order something you don't like, hang on to it, you will probably like it down the road, IMHO. Best of luck!!