There is a class of premium Shopify theme (Dawn, Impulse, Prestige, Be Yours) that does most of what most stores need, and for stores under 100 SKUs with simple workflow it is usually the right answer. Where premium themes struggle is performance at scale (Lighthouse drops fast once you add 5+ apps), bespoke merchandising controls (anything beyond the templated section list requires a developer anyway), and SEO signal architecture (schema, content depth, internal linking patterns) that the off-the-shelf themes treat as afterthoughts.
The trade is: themed builds get you live cheaper and faster, but compound less. Bespoke builds cost more upfront and ship in 8 to 12 weeks instead of 2, but they compound: Lighthouse stays above 90 because every section was written for performance, SEO foundations were baked in so organic growth from month six onwards is real, and your merchandising team can actually run the store without a developer in the loop. For stores above 100 SKUs or above R500k monthly revenue, bespoke is the better economic answer.
Shopify Plus, specifically, opens up checkout extensions, B2B catalogues, multi-storefront, and Functions-based logic that none of the standard themes touch. If your business model needs any of those (subscription, B2B pricing tiers, custom shipping logic, advanced loyalty), the build complexity moves up a tier and Plus is the right home for it. We will tell you in the scoping call whether Plus is genuinely necessary or whether standard Shopify is fine for your stage.