You're not necessarily going wrong anywhere. The fact that you're questioning all this shows you're on the right track.

Yes, you want a higher c.r. to improve efficiency, but like you said, that requires a longer cam with a delayed intake closing point. If you run high c.r. with a short cam, you will build excessive cylinder pressure and nothing short of race gas will prevent detonation.

I just don't build high c.r. motors for the street and try to discourage it when talking to others. For a daily driver or one that needs to lug for towing or other mundane duties, the best plan is maximum 9.0:1 c.r. and a cam that matches to keep the operating range down low where you can use it.