I would just want him to know his side of the operation to the proficiency standards to which he has been trained. Expect them to not forget what it was to be an FO and establish good CRM with their crew especially when it comes to decision-making. But above all understand that if very new to the LHS they might make mistakes and that is acceptable so long as they're in the realm of safety and/or taken care of :)

On the same subject you have captains posting with just over a years experience in the LHS with captains posting who have more than thirty five years experience of the LHS, so you can expect anecdotal experiences and expectations right across the spectrum from one end to the other and a fair amount of disagreement. :)