I've spent a few minutes poking around ArcGIS Pro. Two questions I have already are:
1. Are you able to set up grid lines in the layout in order to align multiple data frames with each other?
2. Are you able to use the custom styles in symbology?
Regarding your first question:
Snapping grids and guides and such for layouts have not been implemented yet. They won't be available for the first release. For now, you can use the ribbon to edit the X and Y positions and you can use the Align commands in the ribbon to align elements to each other.
Hopefully someone else will chime in with an answer to your second question.