On United 787-9 Polaris seats, bulkhead (Row 1 and Row 9) have full sized footwells for both window seats and center pair seats. You’ll also have a nice shelf in front of you which is handy to store all the extra blankets/pillows/mattress pads.

Odd row seats are generally nicer since they are facing forward so on the window side you can look out and be further away from the aisle. Even row seats you are exposed more to the aisle and on the window side will be looking away.