Oof I'm 6 years late to the conversion, hey guys how's it going? I hope business is booming.
I built an app to split test themes (it also does products, but themes ya ✊).
It's called Theme Scientist: https://apps.shopify.com/theme-scientist... because when you test and measure results, you're like a scientist haha am I right?
Anyway if anyone needs ideas for A/B tests on your store give me a shout I'm happy to help.