yup.... to all the things you said. It will happen, and probably soon. I think I wanted to have tried a variety of flavours before jumping in because, you know, you could potentially buy lots of different flavourings then discover you don't even like half of them. About a month ago I spent practically a whole day surfing some Canadian websites that offer DIY supplies and at the end of the day I had an order put together for over $250. lol *reality check* I think now I am much closer to knowing what I like and don't like so I could probably go with less flavours and still get a good start.
About the flavours, just wanted to add, there's some flavours that are the "basics" that every one usually start with, while others are more for background taste, and some meld together, others, not that well. Once you start DYI, you'll probably find combinations that work better for you than others.
There's recipes sites that are truly assets to get your bearings, to get the average used for single and for recipe mixes, but keeping in mind that most recipes are as per that person's taste. They are good starting grounds to build on though and should be considered examples and guides for the most part.
The most popular site would be : https://goo.gl/QvM89r
And yes, once you start, you'll find that the amount of flavouring is just boogling... easily in the thousands, and one flavour from brand to another will differ.
So I tend to recommend that you check out a bunch of recipes to get an idea to the flavours that you'd be needing before ordering.
Side note: There's the fear-mongering about diacetyl and pop-corn lung, but it's already proven that even the flavour/liquid with the most diacetyl doesn't even come close to what a regular cigarette contains, and no one has even gotten the dreaded pop-corn lungs from smoking. It was exposure to thousands of times more, plus that they aren't even sure that it really was diacetyl, or at least by itself that caused it, there is still not a single iota of proof after all the research done about it, just guesses and beliefs.