1. I would expect galley service to be pretty standard. The main PE meal is normally based around the J meal so similar prep.
2. I have never had any trouble jumping the aisle pax when in a QF window
3. Block should hold as long as low loads. As you are relatively low status I would expect yours to be one of the first to go
4. Bulkhead in J has heaps of room - remember the bed has to extend out into that space... Advantage of upstairs is the extra side bins which provide good inflight storage