My sim partner was a KC-135 guy that had been flying drones for the last 4 years. He was an excellent stick and rudder right from the start (probably better than I showed even after years in the plane) His biggest issues in order seemed to be,
#1, justifying being there when he saw his paycheck of about $700 takehome twice a month. (he was an O-5 making a lot more than that in the AF)
#2, The extra "outside the cockpit" considerations, such as communicating with OPS, Dispatch, Flight Attendants, ect.
#3, Dealing with flows instead of everything being read/do.
#4, Passengers that didn't obey orders.

Overall a few months on line and he'd be fine, but no way should he (nor did he want or expect) to be a captain day one.
He was here under a year and bailed to an all freight, heavy jet operator. (home virtual basing and see #1 and 4)