Well, you don’t have many exercises and you are only hitting certain body parts once a week and neglecting some at the same time.
Even if your motivation is lacking, I would recommend two full-body workouts per week. I believe Ian King wrote an article like that a couple months ago. CW also had a great two-day-a-week training program in a previous issue of Men’s Fitness.
Your set up won’t accomplish a whole lot unless you’re doing 10-20 sets of each exercise, and even then, you’d most likely barely maintain. Not to mention that you’re not training often enough or covering the whole body.
You’d be amazed at what two full-body workouts consisting of 4-6 exercises could do for you.