Hello,
I'm French and i studiying roman architecture since several months.
First, i congratulate you for your wonderful models !
I am fascinated by old architecture and I have already made a model of architectural complex of Pharaoh Sahure to Abusir. I also started to model Persepolis since winter 2008 but never finish.
Here are some pictures of my work :
Your models are very interesting but do not have the right proportions. I have studied many texts and also Vitruvius. His formulas do not work for all but we can get some interesting values such as intercolumniation or height of columns depending on the type of building.
I set some rules for obtain a building with harmonious proportions. This one tries with the Temple of Vespasian :
You must first determine the proportions of columns and entablature.
The entablature of Vitruvius is not appropriate for a Roman temple. However, you can follow his instructions for the Corinthian column.
For the entablature, I advise you to refer to the Corinthian order of Vignola.
I do not find attractive method for determining the angle of the pediment or values stylobate and stairs.
Next, you must consider the values between the columns proposed by Vitruvius and height of columns that refers to each of them.