Yeah the issue with the [A] short cut was one of the first things i noticed, and it's actually on of the most used short cuts (at least for me), before if i needed to make changes to the whole mesh (scaling etc.) i could press [A], make the change, then press [A] again to clear the selection, now to clear the selection you either have to right click another face meaning there will always be on face, edge, or vertice selected, or root around in the header menu to find the select none option.
I've noticed this with a lot of the changes to shortcuts, they do't make it easier or quicker, they practically double the workflow in number of clicks, button presses, and time.
They've also removed the textured view so you can't preview your baked texture without setting the baked texture up as a material, which is a whole other set of nodes and settings, now tripling your workflow.
Also, the new Eevee renderer has no texture bake options, so you will have to use cycles which again is extra workflow because you have to set up nodes for the textures and materials, and then set up another set of nodes for the bake, plus cycles has always been rubbish for texture baking because it tries to combine textures instead of just bake a diffuse texture.
Oh and they have removed the Blender Game Engine, which doesn't really effect us, but is annoying quite a few people who have been developing games with it for years.
i7 7700,k NV1070 8GB, 16GB 3200mhz memory, 1x 2TB Hybrid, Win10.
i5 4760k, NV960 2GB, 16GB 2333mhz memory, 1x 2TB Hybrid, Win10.
i3, Intel 4000 series graphics, 6GB memory, 1x 500gb HDD, Win8.1.