I believe that your website has an identity. This is your site 'brand' and it tells visitors about your site's personality. Your site design reflects this personality and every page does this consistently, so there is no question in your visitors minds that they are on your site.
Your site brand is defined by the colour palette, fonts, image style and copy writing rules you've chosen. Consistent application of the brand guidelines across your site ensures trust in your site and is the first step to creating a relationship with your customers. So, your design should look good and professional. A design can be fun and still have a professional look.
Mobile support is critical for a web site these days. I use the bootstrap grid as a standard mobile framework in site builds with both Umbraco and Sitecore. Bootstrap is an industry standard that is dominating its market niche. It allows for quick support of mobile screen sizes of all dimensions. Bootstrap has a great community and is fully open source, using it on a site build is an obvious choice.
Web search engines are an important resource to help find customers. Getting site content in front of interested parties is an inexpensive and really, indispensible way to increase site traffic and ultimately leads and customers. While SEO is a somewhat mysterious practice, it really comes down to creating a web friendly web site that demonstrates your expertise and authority in your specific field. I truly believe that 'content is king' and a site with strong, relevant and thoughtful content with proper keyword optimization will fare well with the search engines.
Trello is a great tool for project collaboration and tracking. I like to use Trello or Azure Dev Ops for project task management. Standard agile metrics and analytics including burn-downs, and burn-ups, defect graphs and reports provide data driven insight into project progress. Trello provides great collaboration tools to help me stay tuned in with customer requests and provide transparency into task progress.
I believe strongly in full deployment automation. Azure Dev Ops is my tool of choice because of its strong integration with Azure Cloud and .Net. I use Selenium Web Tests to help ensure system stability and speed up development because less manual verification is required.
A prioritized User Story backlog and set of high-fidelity mockups result from the Learn phase
A working website that can be publicly deployed