Space Planning

I have a living room that is very oddly shaped and it's difficult to know exactly where to place furniture. The only really good place to put a sofa would be in front of a ac/heat unit that is under one of the larger windows. The sofa would not cover or block the vents, since they are on top. I really hate doing this. It doesn't look bad though it may make sitting at the sofa kind of too cool in the summer and too warm in the winter since the one unit is going to heat and cool a pretty large area. I know that this is a minor issue but does anyone have any thoughts about this!