There have been people Cain has worked with in the past that he made a good game with he probably wouldn't want to work with again. Also vice versa. Not really Cain's guide to people you should look to work for, just what works best for him.
Five things, not in order, Cain avoids giving things in order because people argue about the order.
Likes working with smart people. Someone accused Cain of only wanting to work with college people, he strongly disagrees. Tech director at Interplay, large amount of Fallout and Troika team didn't go to college. Likes working with people who can think of solutions, plenty of people have thought of better ideas than Cain.
Likes proactive people, can notice there is a problem or inefficient process, and brings it up, and offering to be the person to fix it. Different from being smart, as he's had plenty of people who noticed a problem and asked how to solve it, and then some people who just didn't bother. Once did a performance review for someone who wanted a promotion, and told them they were not remotely proactive enough, told them they were the kind of person who would sit in a burning room and do nothing until Cain told him the room was on fire.
Likes working with passionate people, he knows it has become a negative adjective in the industry, but would rather would with a good person who really cares than a great person who doesn't really care. Passion shows in the work they do, you have probably played a game that is technically fine but makes you feel nothing, Cain chalks that up to passion. There have been games that didn't sell or review well, but he enjoyed making them because of the passionate team. Soul draining to work with a team that doesn't care.
Honesty, after having learned that people in the industry will lie to him. Just wants people to tell him things, they don't think a game element is fun, they think there needs to be a priority shift. People push stuff not because it's good, but because a friend worked on it, people saying they like something they hate just to get on Cain's good side. On the same game, Cain had someone lie to his face about something and when confronted about it, the worker told Cain he was told to lie to Cain, Cain doesn't really think that is justifiable, didn't really talk to him for 7 months. On that project, had told people to let him know if something changed in an area because it was important. Came in one morning to play it, found a change, went to the source control of find who changed it, went to their manager and asked what happened. Manager was told to put it in, was told by their manager not to tell Cain. Considered not telling Cain to not count as a lie. Told the manager he would now check the source control every day to see if everything is as it should be, and if he noticed another unexpected change, there would be a problem.
Communication is the final thing, likes to work with communicative people. Not the same as honesty because Cain has worked with people who don't lie, but also don't say anything. They don't like something Cain proposes, have a better idea, don't communicate it. Biggest frustration with these people is that they don't think of themselves as a problem, if there is an issue, they just say they didn't say anything. People who say something negative and thus giving Cain something to springboard on is more respectful to him. If you're introverted, go to your lead and ask them to bring it up. Cain has also created ways for anonymous suggestions.
TL;DR Cain's ideal team is smart, proactive, passionate, honest, communicative people.