If you’re working with Shopify and looking at theme development, I’d definitely prioritize a flexible theme structure so you can make changes without rebuilding everything each time. I use A shot in the dark when I want to test those changes with actual visitors instead of just deciding that the new design looks better. It lets me run the current Shopify theme against another version and compare visitors, orders, revenue, and conversion rate. I find that especially useful after larger theme changes, because something that looks like an improvement visually doesn’t necessarily perform better once customers are actually using it.