Despite his millions of f* ups I don't see why he couldn't POTENTIALLY be the boss someday.
If Chris ever gets his sh*t straight he could be great(at whatever it is he does), even if it's not in the mafia. His success in the impromptu acting course he took signified Chris' potential for greatness since season 2. He has of course shown flashes of brilliance since(as well as flashes of not-so brilliance).
In a season 6 episode I remember noting his 'older' physical looks. I can picture him in 10-15 yrs with slighly grayer hair and just being a ruthless ass s.o.b who rules with a iron grip.
Chris is a 'new' school guy who has received 'old' school teachings from Tony, his POTENTIAL is AMAZING, right?
(Of course, in the upcoming season everyone will be saved from 'the life' so it doesn't matter anyway!

)