A good gotcha is accepting a swing acrooss to the parallel runway when visual and forgetting the missed approach for the original runway remains in the FMS. Seen this happen a few times at KJFK when originally cleared 13L then offered 13R which is quite a bit closer off the non precision approach. Aircraft gets high or unstable, goes round and the pilot re-engages the NAV mode and all hell brakes lose. Swingovers were a lot easier in early generation jets than the 340's and 777's where someone needs to put a head down to update an FMS when all eyes should be outside the cockpit. Personally I don't accept them anymore, unless briefed and then I fly the G/A if reqired in a basic mode or ask ATC to maintain runway heading.