As Sam says forestry charges are high, the RoK also has quite a few road miles which puts some people off and also it wasn't a round of many championships so it couldn't draw entires based on that (205's were invited but declined for one).
As for rallying in the south east as a whole - the loss of Longcross is a big blow, we had 2 visits pencilled in for later in the year and it was a regular fixture on our calendar. I've started looking further afield for other venues but you're starting to look at overnight stays and the added cost they bring. New venues are needed - but where are they going to come from? Pressure for housing will kill of some prospective venues and noise issues will stop others being used.
We were planning on doing the RoK this year but obviously not having the car any more killed that one off
We've only done tarmac up until now but fancied trying out the local forests.