For heavier riders The Spleen 159 or 164....PERIOD
see reviews and discussion at
http://www.airpadrekiteboarding.com/...wforum.php?f=2
I've taught lot of lessons on these boards and ride them now for my personal enjoyment. The Lightwave 169 used to be my top choice as a learning board, however mst people would outgrow the LW169 quickly, whereas the 159 Door is such a versatile board that you will never outgrow it. The 164 is a bit wider and may have some limitations on performance and maneuverability, unless you are a really big guy..
IMHO most boards wider than 42 tend to be very bouncy. The flex dynamics and outline shape of the spleene overcome these issues.
good luck.