"Counsellor Worf" has an interesting ring.
He will beat you until you get over your emotional problems.
But let's play...
Picard could easily get promoted to Admiral, but a less ambitious Picard could easily become a science officer or operations officer.
Riker was supposed to be the captain in training, but was stated to be "the best pilot." I couldn't see him being an engineer or science officer though.
Data would be an awesome science officer or engineer. Really the only job I see him being unable to do is Ship's Counselor.
Worf could get by playing as XO or Operations. Obviously anything in blue just isn't going to work.
LaForge was already a decent enough pilot, but could do well at Ops too. We already know he's suited for command in the future. Only field I see him not taking well to is Counseling and Medical.
Troi... let's face it. I have no idea how she was a lieutenant commander to start with, nonetheless made commander. She wasn't even that good in her chosen field to be honest. Piloting... she crashed the Enterrpise... twice. Tactical... no... Operations and Engineering obviously confused her... Medical... assuming she studied a lot it's possible... command... anyone remember how ineffective she was in Disaster?
Crusher... she always struck me as the ship's science officer along with Data being there wasn't a full time one. She did alright the few times she was in the captain's chair.