With meagre support from the West so far - never mind for a completely "secular, democratic Iran" - your point is well taken.
Much will rest with the Iranians inside Iran. They have this chance, hope they won't screw it up again.
If Iranians, INSIDE IRAN, will be happy with "an Islamic Republic Lite", then we all have to live with it. But mostly, THEY, the Iranians, Inside Iran, will have to live with their choices.
From a pontential "Islamic Republic LITE" point onwards, personally, I will not want to hear much about Human Rights violations, dubious elections, and all other nonsense anymore in Iran.