I absolutely understand the idea of giving your wife the responsibility for accepting the issues of the marriage and following through with the counseling to show her willingness to solve the problem. However I think mrscac4 and Lillie make good points that IF she also has to overcome another issue of hers (introversion) aren't you just setting her up for failure? Or at least setting it up so she has to use a lot of energy getting over this particular issue and so this issue is additional to the sexual issues instead of keeping YOUR issue with the marriage clear.
I say this as someone that does not understand the phone aversion issue at ALL. My XH did not like to get on the phone or talk to strangers and he was not an introvert. Anyway, I think of it as if someone took my issue (fear of heights) and told me I needed to walk across a narrow suspension bridge over a 500' canyon before going to marriage counseling in order to PROVE that I wanted to fix my marital issues. I have to say that as much as I would have wanted to solve our marital issues, I am not sure I could have simply overcome the fear of heights that easily or quickly. And not overcoming that fear would NOT have meant that I didn't want to fix my problems.
You wrote: This time around, I want her to think deeply about what she wants out of counseling. What problems does she have with how I behave toward her? Does she have deep wounds that need to heal before we can move forward? What are her feelings about sex in general? About sex with me? None of these are my questions. They are her questions, and she needs to own them.
You have laid out a pretty hefty list of things your wife needs to do. And on top of that you also want her to confront another issue with phone calls/introversion. I guess I would have to ask you which is the larger problem in your marriage – your wife's introversion or her issues with sex? Would it be okay with you if she stayed introverted and uncomfortable with phone calls IF she took on the responsibility of understanding her sexuality? Would it be okay if she called and scheduled the appointment but still was unable to figure out her issues with sex? To me, that is how I would decide what was critical in this process.
But what is happiness except the simple harmony between a man and the life he leads? ~Albert Camus