Perhaps few people would write plugins for LeadWerks. But let's say, if a person is working on a serious project in LW then it will be easier to sharpen the engine for their purpose.
For example, in LW bad editor primitives, poor editor terrain (although it is possible to alter and by changing the shader processing), and more. For example, to make the roads or rivers editor (if waiting for the official implementation, this can take a long time, but to do a simple tool can be quickly (I wrote this, but visualization was only in the game -. Which is very inconvenient)