For clarity, I don't think Ejim should be excluded because I think Cain should go in first. I think Ejim should be excluded because he was a great but not spectacular player over his career. That's personal opinion, and it obviously depends on where you set the bar in terms of stats, how highly you value certain awards, and how restrictive you feel jersey designations should be. Don't get me wrong; Ejim was one of my favorite players. He just doesn't reach my personal threshold to be among the most exclusive group of Iowa State basketball players.
Separately, I think Cain was a spectacular player who deserves to have his jersey honored. I think it's unfortunate that he's overlooked in these discussions. I compared his stats to Ejim's for reference, but they can easily stand alone. As I mentioned in my first post, he averaged 19.5 points and 12.4 rebounds per game over his three-year career (which rank #5 and #2 at Iowa State, respectively, and make him among the very few to average a double-double). He holds Iowa State records for rebounds in a game (26), rebounds in a season (396), rebounds in a season per game (15.2), and double-doubles in a season (22). Cain isn't without honors or intangibles: 1968 Big Eight Newcomer of the Year, 1969 & 1970 First-Team All Big Eight, Iowa State Hall of Fame inductee. On top of that, he was an outspoken advocate for civil rights and social progress and had a regular column in the Iowa State Daily to reflect on those topics. Cain deserves more recognition and, in my opinion, should be at the top of the list for honoring jerseys.