Even though my father is the one that got me into reloading, and he's an experienced reloader, I was extremely cautious when I first started out, even though I had his guidance and knew he wouldn't let me do something stupid. For the first couple years, I wouldn't have even considered loading for an AI or wildcat cartridge that I couldn't get "book" data for. For the first few months I preferred staying with loads where I could use the exact components shown in the manual. Now, about 6-7yrs later, I'm not nearly that cautious and I'm willing to experiment a lot more. Of course I don't do crazy stuff, but if I can just get a ballpark figure on how to load the round, then I'll just start low and work up. I'm not scared of having to "work up" a load for something I can't find concrete data on.
Although I have always loaded with accuracy in mind, I do load hotter than I used to. I'm still not one that loads rounds so hot that they normally flatten and blow primers, but I have no problem working up until I start flattening primers and then backing off just enough for it to go away. Of course I keep in mind what type of temperatures the rounds will be used in when loading like that too.