In season 5 Silvio couldn't even remember why Ralph killed Tracey, so it's definitely not a problem. I think Ralph would of been a good boss because he did have business and street smarts. Most importantly, he was a great earner. However, he was a loose cannon and it would of led to his downfall eventually. Also nobody really liked Ralph so it's questionable how much loyalty he'd command.
All Day nails it about Ralphie hiding money from New York. The jokes about an underboss's wife. Ralphie was more cut out to be a serial bank robber or con man than a wiseguy. He was Jersey's Joe Gallo.