I am finding that splitting and merging of viewports to be particularly much harder in 2.8 than the previous versions. Especially merging grabbing from the corner and pulling down ) most ofthe time ends up with splitting the windows further. I think that this is an isue of the grab/area area to be way too small to do this comfortably. This is expecially pain in the neck on laptop with with a touch pad. I have harder time with this when I am not using a Wacom pen. The precision required to get this going is a bit too demanding.\
Trying to get that "+" so one can do splits or merges takes minimum couple seconds for me. In 2.7 this si no issue because there is a visual (stacked diagonals) indication of where the mouse should press to initiate the action.
Just last night, I ended up with 10 unintended horizantal splits on my Laptop, and trying to merge all that back was even harder and painful.