WHOA, NICE!!!
The Excalibur came out pretty well, don't worry! I think you just need to crease the points on the "petals" to make them close up a bit more. I don't know how else to make them close. In the meta model, the crease line runs all the way from the point to the middle of the rear of each petal. Tell me which parts did you have to figure out further, I'll revise the instruction graphic.
The Delta looks shiny, did you use metallic cardstock?