Rak - I hate to tell you this, but you've got the KKFever and there is only one known cure. Buy your girls a KK of their very own!
Okay, to answer your question, I've cooked on multiple levels of TheBeast, my KK BB 32". It's really a snap to do, and as Robert so rightly points out, once a KK gets heat soaked, there is little difference between grill levels.
I tend to like to keep like with like, i.e. always cook pork above pork or beef above beef. Thus I'll cook spare ribs over butts or beef ribs over brisket. In TheBeast, the main deflector sits atop the rails of the charcoal basket. I've done a couple of turkeys on the lowest grate, a fair number of chickens on the main, and quite a few Cornish game hens on the upper. No big deal. This cook was for a fund raiser for a Men's Organization at my church. Everything came out moist and beautifully brown.
I've never had to worry about recharging lump during a cook as I always start each cook with a FULL basket. The KK is incredibly efficient storing a tremendous amount of thermal energy in its refractory and then radiating it to the cook. I generally heat soak for about an hour before putting the cook on the grates.
So not only is cooking on multiple levels practical, it's just dadgummed easy.
Hope this helps in your decision to buy Aashni her own KK!