Glad to see this got moved out of the Boot Guys forum.
Absolutely, you should get Booster straps for your AT boots. It is SO much better than the stock nylon strap when hiking/walking/climbing. With my Zzeus boots, I've tossed out the laces for the liner. I hate laced liners anyway, so this makes me happy. I might put laces back in if I were going on a long tour and thought I might want them for wearing around camp or just keeping liner snug when walking long distance, but for 99% of what I do, the booster strap works wonders. Heck, I even leave them clasped when driving in my ski boots (short distances, don't worry).
I'm 200lbs, 5'10", not overly aggressive skier. I have the "Expert" model. I'd suggest either the Expert or Standard for you (probably expert). Don't get the WC model.