Some things to think about when placing winches:
Body Placement -- can the person cranking the winch
position themselves and brace themselves well for maximum leverage?
Swing Radius -- can you swing the winch
handles all the way around without banging your knuckles on anything?
A Fair Lead -- where is the line that is to be winched coming from? Make sure the angles (both horizontal and vertical) work!
Structural Support and Mounting -- winches, particularly genoa
sheet winches, carry some of the largest loads of any hardware
on the boat; to what are you going to mount the winch?