In FC, there is some under-seat storage in window seats, but for the aisle's there's hardly any. Well, there's 'no-man's land' in the middle and one could politely ask to use it! Personally, I would offer the middle space to the person sitting by the window if I have the aisle seat since it's my courtesy for unintentionally blocking his/her path.

For the bulkhead, I sometime prefer it since there's nobody going to recline into my face. Least to say, my drinks would come first before anyone else's!