Let the Lord guide and lead you as you work through what it means to have a Christian marriage. Your concern about sexual practices is an important one, but only part of the bigger marriage picture. To me, once a week is not only not enough, it's not spontaneous enough. I tried to understand that this is just who she is, but I'm starting to resent her. The differences in your libidos as husband and wife are not unusual.
Many couples disagree on the frequency issue.
But I think a key to reaching your wife, who likes order and predictability, may be to communicate your desires and frustration in a different way. Try writing her a careful letter expressing your love and desire to be a thoughtful husband. Point out the things you appreciate about her. Open, vulnerable, straight talk about your feelings and desires is your best chance of getting your message across. With that preamble, talk to her about male sexuality in general.