Any three of them are possible. Maybe not entirely trivial but not very hard either. You will have to do some thinking about how context is defined and implemented of course.
As for how to implement the left toolbar: in essence you could copy the right toolbar and add some suitable CSS to create a right one (there is in fact fully working CSS for a three column layout with the standard design when you have nagivation left, content middle, toolbar right and it's quite easy to get it to be liquid, too [1]).
It should likely be possible to do without any PHP coding but prepare to dig into template language quite a bit.
[1] essentially you have to change the width of the all encompassing div ;)
PS: I have chosen ez over typo3 for much the same reasons ;)
