Do you think saffron can be substituted with some other spices?
I don't think so.
Being the expensive spice, I guess people would think of substituting it with some other spices, to get the flavor or the benefits of saffron. But, the ultimate reality is, nothing can give you the same effect/aroma of a kesar because, it is very unique of it's kind and it has it's own property that is not available in any other forms.
I would rather lose my curiosity in finding the perfect substitute for the precious spice.
So, how about you? Incase, you did find a perfect substitute please do share with me.