Like you, I used to shy away from doing anything other than field stripping but especially on newer guns where replacement parts are easy to find (should the worst happen) I find myself exploring a bit more. I suppose I'm thinking about my J-frame (revolver) and M&P pistol. After you do a little reading/looking, going a couple steps further can really help you understand your gun better. And should a malfunction/breakage occur, you have a bit of a hint as to what parts when wrong. That would be a bit harder to do if you didn't have an understanding of how the parts interact before the problem came along.
+1 on starting with slides/striker mechanisms.