Though the result certainly looks great at first sight I'd wished there had been a really "solid" construction using basic and repeatable shapes "behind" it all. Doing all this based on tracing a more or less rough sketch seems sort of risky to me as some indepedent "fiddling around" (just) by eye in some areas becomes necessary to make it all fit in a way. However, once you know where to look you see that it actually doesn't exactly fit - e.g. as curvatures don't really match the way they should if his object - even while impossible - should be perceived as sort of "true". That being said let me repeat that this certainly DOES look nice but I'd be ever so curious if there actually is a way to get it "really" fitting using a more constructive approach.