I have written the same post as Justine many times over the years on these forums. I lift for strength for the upper body and with greater variety, more for endurance, for the lower body.
In theory, heavy lifting is supposed to give us incredible lean muscle all over and a tighter body. But, that is not the experience of every woman. So, what gives?
There is no one solution. Also, there is no short cut for experimentation on your own. Every Cathlete could chime in here with what has worked for her but none of us are you, so you have to start playing around with different programs and approaches and find that winning combination of workouts types, weights to cardio ratio, lifting type, and approach to nutrition and also daily movement quotas (excluding actual exercise) that gives you the body you are comfortable living in.
Once you have that, bear in mind that our bodies change as we age, so what works for you now may not work forever. Stay flexible and keep tweaking.
Cathe herself might tell you that one of the best things you could do is to simply change up your program every month or so to keep your body guessing since our muscles do get used to certain movement patterns and the resistance placed upon them. What works now won't give you the same results in 6 months time. There is certainly nothing wrong with abandoning a program that is not giving you what you want and making you uncomfortable in your own skin. Your workouts are your passport to greater health and enjoyment of the body you live in. You are answerable to no-one else regarding the fitness decision you make and your daily fitness practices.
Personally, I have never been leaner in the lower body than when doing long distance backpacking or frequent distance running, which translates in the gym or in workout-speak to weighted cardio and long, endurance based cardio. So, workouts and Cathe programs that work for me are all step workouts, running, powerwalking, metabolic conditioning, lower body training like Leaner Legs from CTX, Xtrain legs, Lean Legs & Abs and Great Glutes, and Slow & Heavy for upper body.
We are all different.
Just re-reading your post again, you know, there's also nothing wrong with using the STS program as YOU wish, i.e., no-one is forcing you to do all 3 mesocyles, or to finish them all, etc. You might, for example, start Meso 1 and love the results. If you do, stay where you are. if you want to start Meso 2 and see what it does for you, then by all means. If you don't like it, then stop, or keep at it for the upper body for greater strength, but stay with Meso 1 for lower body, or keep Meso 2 for upper and start introducing the plyo workouts from meso 3 for legs along with Meso 1 for lower. There are many ways to work it.
Clare
If you do feel ike you need some extra, I would just add a Kickbox dvd. 
