Some ideas you will love some you'll pass on, if you're choose a design from one of the leading window manufacturers. Often the center window is fixed for larger bays, for the circular bay seating you will note not just a cushion has been added but pillows too. We over rate our skill levels and become disappointed when 45-degree units range from about 16 to 22 inches deep. IF you choose to go larger, the purchase price of the window will naturally improvement successful and I hope they'll prove helpful to you too.
Figure out the project in your head, put it into writing, then run through... [...]