Is your feature request related to a problem? Please describe.
There's a + sign that shows up next to a block. I think it's great because if I have multiple long blocks, my mouse cursor doesn't have to travel all the way up to the toolbar:

However, I was confused on how I could get it to show up again. @karmatosed pointed out that I'd have to hit return, but this wasn't intuitive to me.

I think part of the reason why is because the + button is being used in two different ways depending on the context: on the toolbar, it adds new blocks. If it's next to the block itself, it can also change the type of block (e.g. Paragraph to a Quote) then automatically adds a new Paragraph block beneath it.

Maybe this is even just a verbiage issue since it says "Add block", but the action of adding a block is fulfilled by hitting enter, not by clicking the + button.

Describe the solution you'd like

Apart from hitting return to add a block, maybe clicking on the white space beneath the block adds a new block under it.