Update the Classic Designer Controls to look the same as the Responsive controls
For a consistent look and feel to forms designed in either of the designer choices (responsive of classic) it would be good to update the designer controls to more closely reflect the look and feel of the new responsive controls which have a modern, clean and fresh look to them.
Thanks for your suggestion Ryan. I can tell you that the new Responsive Designer will look very different to classic when Universal Forms will be released as its a new engine.
Once we release Universal Forms for SharePoint, we will revisit our strategy around Classic Forms.
I can see why the two designers are different. Responsive designer is more for simple form designs. I like that the classic designer doesn't have a restriction on the number of columns you can have, like responsive does. However, it would be nice if the classic designer had a bit more of a modern look like the responsive designer does.