Overlooked

Help! The people that live behind me have today taken down the conifer hedge that divides us leaving me with just my six foot fence. Plus side is that I don't have to perch on top of the ladder to try and trim back, and I have more light. Negative side is that the ground level behind the fence is a foot higher so I can see everyone's heads as they walk to their cars (parking spaces behind fence). I have no privacy now. Going to put a trellis on the fence, but is there anything that I can grow quickly at this time of year or what can I plant in the spring? Also thinking of maybe a cherry tree to add height. The garden is also a stupid shape (like a triangle that you get in a maths set) with this part of the garden being narrow so don't want to have anything bulky.