Getting a Shopify theme ready for submission is not just about making it look finished. A Theme Store-ready build needs to behave properly across a wide range of merchant situations.
The theme needs clear templates, reusable sections, sensible settings, good defaults, accessible markup, responsive layouts, and clean code. It also needs to handle awkward content: missing images, long titles, sold-out products, sale prices, pagination, filters, empty states, and different product variant setups.
Theme Check is important, but it is only one layer. A theme can pass automated checks and still feel unfinished if the real storefront experience has not been tested.
For ID_within V1, I am treating the demo store as part of the QA process. Products, collections, blog articles, pages, and search results all help expose what needs polishing before the theme is properly finished.
The goal is not to build a theme with every possible feature. The goal is to build a reliable V1 that is clean, useful, and easy to extend.