For emphasis, I don't mean to argue hit factor isn't a good way to train and measure progress. I am just offering up my preference to the open ended question of how to approach improvement from the OP. Or what I interpreted the question to be.
Take C hits for example. There are "good C's" and "bad C's" as my coach calls them. On the VTAC target you can see the USPSA scoring lines marked over some anatomical features illustrated, and a lot of Cs are just horrific poor.