Streamlining can be good, but you do risk that everything becomes equally accessible (read complicated).
I was not aware of the F9 and F10 shortcut as I have always used the Context menus to reach those, and F9 and F10 are not described there (UI inconsistency btw., but thanks for the pointer).
An example, Create a class, name it and set stereotype to "control":
EA10: Create class (F3), type name, press TAB, type "co", press DOWN (control is found), press ENTER.
EA12: Create class (F3), type name, press TAB 4 times, press ENTER, press TAB, type "co" (control is found), press ENTER.
Another thing that has irritated me for ages: Reading direction of associations! - If I choose to set a reading direction, it does belong to the association name in the model, not just the visual representation. So having multiple diagrams with the same associations visible, I have to set the reading direction for each and every association. And even worse if I change the name and its semantic, e.g. "has >" to "< belongs to", then I have to identify and change the reading direction on every visible association.
I currently have customers with non-technical staff who are very reluctant to use EA as "it's too intimidating", and I'm in the process of finding out how I can make MDG's for them, but that in itself is quite a journey.
When I used the word "slow", I meant that the application itself has become slower. Load of a simple model with EA10 takes 36 seconds, and the same model with EA12 takes 46 seconds, and I cannot see what I get for this extra delay - The only visible is a "fancier UI", which btw. in both versions I have set to the same XP style without whistles and bells (i.e. no gradients or shadows).
To me, a modeling tool should not trade speed for "whistles and bells". It'll be ok as an option when rendering images and reports.