One tip: Before you place your first DIY flavor order, you might want to order only those flavors you will need to make 3 or more recipes. Order all the flavors for those recipes. Very few (2-3 flavors out of a 50 or more can be satisfying as single one flavor mix) flavors can standalone.I haven't really looked up good recipes yet
After I receive the flavors I test them as standalone single flavors. These tests are important because they will give a feel for taste and strength (note taking is a must for me) , not necessarily if they taste good, but more on how they might interact in a mix.
Might be way too much for nic/liter. Not all nic is created equal and taste is individual. Gallon, if you are sub ohm'g maybe.A liter of nicotine and a gallon