If you enable double click to edit text and dimensions. Plus enable full tool pallet in Layouts, Rhino for MAC would be a commercial product. Not being able to finish off design to the detailed 2D level, is still crucial in manufacturing and production.
if i understand you correct you want to double click the text and then edit it directly in the viewport? at least i hope that you mean that and would be lovely indeed while increasing the workflow of course, nothing worse than having a mouse firework to click on text then go to the textfield to edit it there, its complicated and time consuming.
You could always create a pop-up with your favourite tools, and dedicate a mouse button to it (macro: _ShowToolPalette _ToolPalette=Popup _UnderCursor=Y You can use any name instead of “Popup” when you have created a tool pallet with a different name). After all, there should not be many that you need to “finish off the design”, as you say. Text editing is cumbersome, I agree.