I've got some answers and some questions for you.
I have two Caldera Cones and both the older style Esbit stand (just a U-shaped piece made from a thicker hardware cloth-type wire with smaller holes) and the Gram Cracker. Both of the Esbit stands put the top of the tablet about 1.5" from the bottom of the pot. I have consistently brought 2 cups to a boil in my SP600 with less than 9g of fuel using the Gram Cracker. Unlike what someone mentioned earlier, I find the Gram Cracker makes the tablet burn slower and cooler, but more efficiently. I achieve faster boils times without the sides on the GC, but use more of the tablet (the only brand I've used is Esbit). With a Titan kettle's wider bottom you might use even less. It is excellent for heating water, but would not work well for simmering.
Which leads to my quesion: are you sure you need to simmer? If you have already soaked it for 30 minutes, would it work to just bring it to a boil for a minute and, as others have suggested, put it into a cozy to finish? A Reflectix cozy is very easy to make and cheap. And while most of the soot left by Esbit on the bottom of the pan easily wipes off with leaves, dirt or sand, storing it in the cozy in your pack takes care of any worries about getting other gear dirty.
I would suggest you experiment with just bringing to a boil, then immediately put in a jacket or something else to keep warm. If you find this works for your meals, Esbit might be a good option. I highly recommend the Gram Cracker, well worth the $12 (IIRC). If this doesn't work for your meals then maybe an alcohol stove with a simmer adjustment would work better.
Remember, figuring these things out is half the fun! Good luck.