Your best bet is to search through available staff and look for high determination, man management, judging ability and potential, motivation, level of discipline and then any specific coaching attributes are a bonus. Being that far into a game and as every game is different, it's pretty hard to actually suggest somebody to appoint, as somebody who might be amazing in my game, may not have turned out so good in yours and may have retired. Also, there should be plenty of regen staff and ex players who have become good staff. For example, I'm in 2017 and Emile Heskey has just managed Blackburn to a 4th place finish in the Premiership. While in real life, he'll fall over in the interview and won't gt the job.