Since we have a Celestia discussion going on what's everybody's headcannon on her degree of governmental power?

On one end of the spectrum she and Luna are absolute rulers whose word is law and decrees absolute. At the other end their titles are mostly ceremonial and the bulk of actual government is done by mortal ponies. Most of Celestia's influence comes from being so beloved by the common pony that being seen disrespecting her or flagrantly ignoring her advice would be tantamount to political suicide.

Personally I think they have something like a constitutional monarchy with division of powers and checks and balances. With Celestia and Luna acting as the Executive branch while an assembly of mortal ponies is the Legislative branch.

If you're wondering I have asked this question before. But it was what, 20 threads ago? So I think another go is fair.