As far as the 777 is since I'm not an FO I can't tell you their preferred destinations other than the obvious ones such as SIN and EZE ..
Anyhow to answer to some of your other questions...
Even with a blind line, are you allowed to trade with other FO's?
AFAIK Yes but I'm not an expert on that - I believe there might be problems with credit transfer if you're trying to trade with a Tripline holder.
Even though there is no guarantee of success, can you specify a particular start time or end time for a particular day? (In theory could you request for example; Saturday nights from 6pm onwards, or request to work every Sunday)
You can certainly submit blindline preferences but at the moment at least Pre-Ops (scheduling) build the Blindlines from the selection of whatever trips are left unallocated
after all the Triplines have been put together, so their/your choice is limited. Best you might expect is a result from a broad preference such as "long trips preferred", or "LHR trips preferred". I certainly think you'd be very lucky if Pre-Ops actively considered a preference for start/end times....but you can always ask....
Do you also get to bid for your annual recurrent sim training slots?
Annual? I wish! It's six monthly - Yes, you can submit a preference for certain days, and training admin might try to comply with your wishes, but again no guarantees - you often get something out of the slots that are left after they've rostered those on courses....