I really enjoyed McMafia and thought the BBC did a very good job, yet to an extent that I do agree with
@coollino that it was a tad predictable.
It epitomised the whole Michael Corleone character theme: an individual who is determined to not be in the family business but forced into it...
...which ultimately makes them more ruthless than their counterparts. It's not success that drives them yet rather it's the survival of their family.
If you change the time, location and characters then it isn't much difference from the Godfather really, hence why the ending was predictable.
If they do make a second series then I'm sure it'll be his (Alex's) further dominance vs. his distancing from his family *cough*Godfather II*cough*.