I've mentioned this feature request during final Idea 5 testing, but it was a time of code freeze. So, I want to try one more time.
I suggest to create different layouts (or a switch) for tool windows (I'd like to see this for debug window first of all) that puts buttons (step over/step out/etc) on left side of panel or on top. When this tool window is pinned to bottom, I'd like buttons on left side. And when it's to the right for example, buttons on the top would be better as I think.