Okay, first of all, you didn't use the Builder Application template (
http://www.opticraft.net/index.php/topic,4.0.html)
Second, here is my opinion: We have high standards for quality of construction, Your builds are good, but we expect to see better results. Practice different building techniques to make unique structures (
look at some infrastructure pictures on the web, or examine buildings from your home). Becoming a builder requires you to analyze and figure out how to build something taken from a real life perspective and making something extraordinary from that mindset.
I would not like to lecture on about this, so please bear that in mind