A cynic might say that Collins did not live long enough to disappoint. A Collins who survived the Civil War and played a major art in the early development of the Irish Free State is interesting. I couldn't even gues at how the country would progress. Would he be an internationalist? I simply don't know.
Perhaps more a realist than Dev and willing to make compromises to play the long term, from memory wasn't it he who said that the Treaty didn't give Ireland freedom but the ability to achieve freedom, or something like that.
Certainly it's a great unknown in Irish history.