You did not miss anything. And #2 is the way to go, #2 is the only feasible way to go in order to achieve an interface that is maintainable, modular, flexible and scalable.
Once you start wrapping native element in user widgets, there’s no looking back.
There’s also no looking back once you start using Named Slots and then finally figure out how the heck widget inheritance works.
And even all the above eventually becomes underwhelming. Unlike Slate, UMG cannot easily produce certain behaviours. Here’s a fantastic post addressesing lackluster UMG tunnelling / bubbling handling:
My advice is: absolutely do, and wholeheartedly, too, embrace User Widgets. 