I can't really comment on away scheduling because I didn't do any, but just a couple thoughts after reading your plan.
-Your Step is fine, so consider if you will do really well on CK before taking it so early. Most people pushed it off so it would not be on their app in case they got another score in the 240s. If you get 260+ easily, then by all means take it so early.
-I found that having a non-ophtho letter didn't help at all - it was never mentioned. If I could do it again I would have had 3 ophtho letters. It sounds like your home PI will be a good one, followed by your home ophtho letter, and probably another one from an away ophthalmology rotation with hopefully a well-known person.
-People apply to so many programs every year that your thought of targeting sort of goes out the window. If you applied to all the midwest, mountains, and south, you would still probably add a few more.
Best of luck. Feel free to PM if you have any questions (matched this year).