I like how Blender is very handy because of its shortcuts and the way its workflow has been studied to allow to work as quick as possible.
I saw you (developpers) are implementing new shortcuts, etc.
I think that’s a great idea ! We should focus on that.
I like Blender because of it and I dislike a lot of graphic software because the lack of it 
I agree,
usability is a decisive question, especially regarding animation software, i.e. shortcuts can easily save about 50% of the production time and even more, in some repetitive tasks. Implicitely, this guarantees a 50% of success; I mean, without a good usability, animation software is worthless.
Regarding Pencil development, I think it would be interesting to discuss about ideas related to workflow, productivity, ease of use and, why not, learnability. After all, Pencil2D is a digital pencil, a versatile pencil for all ages and backgrounds.
Here are some important points I try to keep in mind everyday :
Respect the actual application loading time: It’s excellent, so far.
Increase graphic speed and precision: Especially for brushes.
Debug while developing, I think it’s the most efficient way.
Respect the comfortability and ease of use.
If you think there could be more convenient shortcuts, please, let me know, saying what makes them better ! New ideas regarding workflow’s efficiency are equally welcome.
To begin, I’ve just added two types of Grid, they are very basic so we can discuss about their improvement.
As well, in order to have a better reference for exporting images, I added a permanent crop reference. If it’s giving troubles or you don’t like it, please, don’t be shy and let me know.