Hey, welcome to the wonderful world of Filter Forge! Not too shabby for your first!
One general suggestion, which you might have covered in your update, is to give the users a little more control over the output of the filter. For example, you have one color control. You should first of all give it a name based on what it does, like Vine Color. Then you can add one for the plastery material and another for the bricks.
Another suggestion is on your filter tree. To create the brick area in the middle, you take the vines, blur them, do a threshold, blur them again, and then do a noise distortion. Avoid long chains with blurs (especially with a large radius); They make your filter slow, and really there's not much point to them if you are just going to distort them afterwards.
I'll be waiting for your update. Keep forging!