I think that if you want feedback on specific issues, you need to define what they are. Webflow doesn’t claim that the device preview is accurate across devices. In fact, this is pretty common in web development. The solution is to test on standard devices your audience uses and then make the necessary changes in the designer required to address layout issues. In front of me are two phones, two tablets, a laptop, and a desktop with two monitors. Does that sound extreme? Actually, it’s pretty standard if you’re in the business. Many issues are related to the choices that you make when laying out elements in the designer.
I suggest you identify layout issues specific to a device and then update your post seeking advice on how to resolve it for that particular device and problem. When referencing a device, be sure to include the model and the OS version, plus what browser you are using.