Round corners should not be quarter circles connected with lines.
The eye will spot the connection points so these points need extra care.
Adobe should study how Apple shaved off these points on the icons in the iOS. System iOS 6 had the round-corner-fault but in iOS 7 the shape is much better.
I wish Adobe could give us tools to control the round corners, to shave off these connections points. Old Freehand had this feature. Please bring it back to Illustrator and InDesign.