We're in the step were looking to migrate! Now we have CS-Cart and we want one theme (Maybe Bootstrap?!) with clean code. Our target is if we could find the perfect solution for fast browsing, fast aiming on products and what else? SEO ofc!
I have testing ovet 15 famous themes till now bot nothing special atm.
Be gentle with your answers/comments. I'm in the first step.
CS-Cart is AWSOME!!!!
I have yet to find a magento theme / template that gets a excelent score with Page Speed and GTMetrix.
I've found that the they ask to have the above the fold js defered ...pain in the ass with magento themes.