Possible Clues:

• Roof feature such as on Brighton Pavilion
• One covering tiny particle for Dominic in Russian architecture
• Describes Russian architecture to 21 across at The Rotunda
• Head priest's last to criticise exotic church feature
• Architectural feature depicted by this puzzle's arching circled letters
• Kremlin roofline feature
• Roof shaped like a pungent vegetable, on a Russian church, perhaps
• *Saint Basil's Cathedral feature
• Prominent feature of 5-/17-Across depicted in this puzzle's grid
• St. Basil's Cathedral feature