Trying some one shots and/or mixes that don't need a long steep might be fun. You can get a sense of what flavoring percentages you tend to like that way, and you can get small tester bottles while you are waiting for your longer steeping juices.
I don't believe in quick steeping either. It's just not worth it to me. Etc. You can also steep individual flavors to get a sense of steeping times. You can then use those later in recipes that have things other than long steeping times, like if you are a vanilla hound get a bunch of vanillas steeping and then use them as part base at the right percentage for your recipes.
I have a custardy mix that is still going-- Into some of my other stuff.
Anna