Hi @edbudev, assuming this thread is about the Launch build time.
From experience, I can say that the number of Data Elements drastically increases the build time.
I also had a big project with tons of custom code which build time was acceptable until I started creating more and more DEs which significantly increased the waiting time until something it was done. I would not even say – gut feeling - that the prod build time is much different to the development build time.
Very unscientific, I know. Just from experience I would say, avoid using Data Elements whenever possible and rather evaluate the elements in your data layer which do not require transformation through custom code on the fly.
Hope that helps