Some architectural principals an architect should follow

• Cost effective solution: Maximum benefits at the lowest cost and risk - by using reusable frameworks / libraries
• Business continuity - New changes should not break the application. Minimum downtime for deployment. Rollback plan should be in place. Automated test run to ensure the quality of deployed build. TDD.
• Architecture should compliance with standards and policies - It differed from domain to domain. 
• Should adopt best practices related to technologies / domain in the market
• Information should be security until and unless it is for public use.
• Architecture should be technological independent - SOA based architecture
• Easy-to-use applications - user friendly user interfaces. Get it reviewed by UX expert.
• Component reusability and simplicity
• Low-coupling interfaces - Dependency injection
• Adherence to functional domains 
• Changes based on requirements