There has been one thing that has been requested for so long and should be simple to implement, but has never been done.
That is when MC is run and the Action Window is displayed. That's great, especially for the very first time a brand new user runs MC. The user can then click the down arrow to minimize it and the up arrow to maximize it, both very common actions that the Windows user is aware of. There are even minimize and maximize buttons for MC itself in the upper right corner, in fact probably every Windows program that exists.
If the user decides to minimize it because they don't want it taking up that precious tree real estate, the next time they run MC, it should remember that it was minimized and keep it that way. It still is very clear that there is an Action Window there with an up arrow so the user should understand that they have to click that up arrow to see the Action Window again. After all, they minimized it, and most likely maximized it before to see what it did. Just simply remember the previous state when closing MC.